pissed off with someone
Depends! Sometimes it is SECONDS! Other times? Well, I remember people doing things when I was FIVE that I still haven't forgiven them for. Like miss rose(I believe that was her name) in the 6th grade stealing my apple corer. Or Linda(she always acted like it was her last name). Or a friends mother, etc....
How long do I stay angry with someone?
Not long. If they cross that line, they are gone.
Very, VERY tolerant of others faults, foibles, weirdness, and idiosyncracies. Never judge a book by its cover.
But there are clear lines that can be crossed only once. If someone makes me angry, they will do it again some time in the future. Adult behavior rarely changes. Additionally, if I let it slide once, there is a keen risk that whatever pissed me off the first time will escalate into something worse the second time. The easy way to avoid such stuff is to nip it in the bud at its initial appearance. If people think that you will let them get away with something, they will do it again.
I've lost whole social circles due to one step over the line. Don't regret it at all. My past is like the wehrmacht's retreat from Russia--burned bridges everywhere.
This is a pretty deep topic for me, because I've had two problems with interpersonal conflict with NTs.
The first issue with interpersonal conflict with NTs is that if you don't stick up for yourself, and keep sticking up for yourself once someone starts taking jabs at you, they will generally not stop because something provoked their interest in you in the first place. So you have to learn how to set boundaries and enforce them with people.
All those times with sexual harassers when I expected them to get bored and go away when they weren't going to score, that did work -- but only with the nice, normal, average guys. I got sexually harassed by a lot of guys, but didn't consider it "sexual harassment" because a regular guy will give up in a good mood it's not happening. But it didn't work with the guys who had some kind of mental problem, were acting out some kind of prejudice or they were approaching me as a predator. These were the "toxic harassers." So from my database of sexual harassment experience, I can extract the types: (1) those who harass for some normal objective and when it's not going to pan out they give up with good humor and (2) those who have some kind of toxic, prejudiced or predatory thing going on. The guys in (1) are the normal guys and they are not a problem but the guys in (2) are toxic and they will ruin your job/project/health if you don't take active measures to put an end to their games.
(Below, at the bottom of this post, I will write a note about how to tell the toxic people from the normal "accidental" harassers.)
I find that as an Asperger person, I have no interest in the issues of others unless they overlap with my interests. If someone offends me, I tend to react very quickly and meanly (usually "Bite me"). But then I back off as soon as I realize what I said and after that I usually find it's more interesting to find out what problem the other person had with what I did/said/thought and often times they are right and I was wrong and I learn a lot from engaging with people I've had a spat with. I have very little control over my speech right now, and so I have to be grateful people are patient with me.
But after my experiences with some pathological harassers (more than one), I have been training myself to be a better defensive attack dog against people I determine to be "toxic" toward me. You don't let things go with them (unless they make real apologies, free from "you're <this or that object of contempt>", which they are almost invariably incapable of doing).
When you come across a toxic person, you have to set boundaries and enforce them or you will get abused. If you back down with them, it's an invitation for them to do more.
Before my experiences with toxic people out in NT world, I never cared what anyone thought or said about me. It only bothered me if it was in my face, and only for a short period of time. I have zero problem making friends with people I fight with. But when a toxic person latches onto you, you have a job to do: set and enforce those boundaries. If you don't set and enforce boundaries with those people, they will walk all over you. And it doesn't matter what their pathological problem is -- racism (and you're that race that they hate), jealousy, greed. They might just hate you, your face and your voice! It doesn't matter!
I don't tend to view those kinds of "fights" as "fights", per se. I think of setting and enforcing boundaries with some people in the way you would put a fence between yourself and a neighbor's dog.
All other kinds of fights and disputes, I get over almost immediately because I have zero attention span for social things.
HOW TO SPOT IT WHEN A TOXIC HARASSER ATTACKS
I have learned some cues that helps you tell the people who are toxic (prejudiced, jealous, predatory) and the people who are not. The people who are not can be dealt with just by ignoring them or working out a simple understanding with them. The toxic people, on the other hand, will continue to have at you until you put a stop to it. And you put a stop to it by not letting anything go -- any ambiguous slur, any dig, any remark. If the toxic predator guy tries to say, "Girls like you like to go someplace nice for happy hour, what say we go?" you don't say, "Oh, no thank you." You say, "What do you mean by 'girls like me'. What are you trying to say?" And then you might get something like "Well, you know, hot girls. I bet you like to party." This is the guy who is hanging on your co-workers desks saying, "I bet she really screams when she's about to come". He will fill all your office mates with sleazy imagery and objectification of you as a sex object. The more he gets away with it, the more you will look isolated and demeaned. This person has to be assertively stopped, not just ignored. So the normal "sexual harassers" -- the harmless, nice guys who might just get out line once in a while are different than this guy who is poisoning your environment.
Learning the cues to identify a toxic person who is on your tail is really important in NT world. Once you I.D. a toxic person, you are cursed with having to respond every time they try to stick a poison jab at you, because whatever issue they have will not allow them to let go of their game. With those people, you have to set boundaries and enforce them every time they try to jab at you again (and they will!).
Here's one dead-on, unmistakeable giveaway that a disagreement, an ambiguous insult, or a mistake or a misstep comes from the well of a toxic person: they use the words "you are this <object>" or "you are that <object>". If they are being toxic out of some negative agenda to do you harm, the <object> is some object of contempt. There is no constructive conversation or fence-mending that can take place with someone who uses that language, even slyly. So the toxic mean-girl's "apology" for being caught "mistakenly" spreading false rumors about you cheating on a project might be "I thought you downloaded that some a website I saw, but now I realize that project had the same title but other work. You are paranoid if you think I would spread rumors about you on purpose." and so you are left with (1) having luckily caught and defused the "cheating" thing, but (2) you are "paranoid". The objectifying language, with "you are this" or "maybe you are that" is always found in the pseudo-apology or explanation that follows up the toxic mean girl attack if you call them out or catch them in the act, framing you-as-<object of contempt>. On a psychological level, it signals the toxic person's intent to continue to be hostile, and may even be a Freudian slip.
If the <object of contempt> that they are trying to tag you with is sufficiently particular, it might also reveal the root of the problem that the toxic person has with you. The toxic sexual predator transparently [i]wants[/] you to be seen and visualized (not only by himself but by coworkers too) as a hottie in the middle of having sex, and that is why he keeps suggesting it with ambiguous language. Those are the people you have to slam back every time they sneak in one of their toxic attacks. And when they come at you with a "you are <object of contempt>" or "maybe you are <object of disrespect>" you have to call them on the object, too. Like, "What do you mean I'm 'paranoid', you really WERE going around telling everyone I was cheating. Just because you say you made a mistake doesn't mean I'm being paranoid because you really were telling people I was cheating." (At this point, the toxic person will make it appear that you are trying to bicker with her, again pointing her finger at you. But you called her on her attempt to apply the "you're a <object of contempt>" tag to you.
If you learn to spot the toxic people from the normal people (and the toxic people are hard to spot because they may only be toxic to you because of some issue they have with you, and only be toxic to you), you will learn the secret of avoiding workplace bullying!