Dysfunctional when I was a child; flawed but decent now.
My mom is probably autistic. She was never diagnosed, but I've heard stories about her childhood--how she used to have meltdowns because her sandwich was cut the wrong way, for example--and I observe her adult behavior (special interests, social clumsiness, low stress tolerance, sensory overload) in a way that tells me she's almost certainly autistic. This isn't actually the source of the problem; my mom is eccentric, and her refusal to have me evaluated for autism hurt me; but she might well have done that if she were neurotypical.
What really hurt our family is that my mom is socially naive and doesn't know how to tell when someone is taking advantage of her. When I was two, my father died. My mom nearly burned out trying to raise me and my sister on her own. She concluded that she needed a man to help raise us; so she married an abusive sociopath who had bipolar disorder, knew very well that he got violent when he was manic, and did nothing about it. (I don't blame his bipolar disorder for his violence. I've known plenty of people with BPD, and they're only violent when manic if they'd be violent when they weren't. Mania lowers your inhibitions; it doesn't make you a different person.) So I got kicked around. I got my first permanent scars at the age of eight when my stepdad, trying to make me hurry to get into the car, stepped on the gas when I was in front of it. I fell and got road tar in my badly scraped legs. I still have dark spots there, and couldn't get medical care for it. Mom had to dig the gravel out of my legs with a needle.
My stepdad died six months after he married Mom. When I was eleven, she married again, to another charming sociopath. This one didn't like my intelligence (I had figured out logically that he was lying about being at work and lying about taking Mom's money for college, because he couldn't even do algebra). So he targeted me, but in a more subtle manner. He used to slap me and such, but he always took my glasses off first so he wouldn't break them. He learned that I couldn't take sensory overload, so he used to yell directly into my ears and blame the resulting meltdown on me being rebellious. Eventually, he tried to counterfeit money, and Mom was going to hide the evidence; so I stole the evidence (scraps of failed attempts), called the police, barricaded myself into my room, and held out for what seemed like hours while I waited for the police to arrive. Then I threw the fake money out the window to the police, so they had cause to search the house. My stepdad got probation. He knew that if he hit me again he would end up in prison, so he focused on psychological stuff after that.
I got myself jumped ahead into high school when I was twelve, and worked as hard as I could to graduate. I was sixteen when I graduated and moved out of the house. Two years later, my sister ran away from home to live with my cousins. My littlest sister toughed it out until she was about seven and my stepdad took the truck and vanished.
Mom has always been very afraid of disability. She used to threaten us when we did something dangerous, that we would spend the rest of our lives in wheelchairs. Not, "You'll put your eye out"... no, it was disability that scared her and she thought it would scare us too. She knew I was different when I was a kid, but she didn't believe I was disabled because I was intelligent. In reality, I was taking care of myself about as well as a ten-year-old can when I left home and went to college. I'm lucky I survived.
Nowadays we have a cordial but distant relationship. I don't let her visit, but she calls sometimes to lecture at me. I know we need to stay distant because her viewpoints are ones that make me very angry, and I don't want to ruin what relationship we have by getting into arguments that will never convince her that, for example, it's okay for my aunt to love another woman, or that it's possible to be disabled and happy and competent, or that it's okay to go to a doctor instead of eating all the herbs you can get your hands on. In general... I can't hate her. She simply doesn't have the social savvy to resist being convinced by people who sound, to her, intelligent and persuasive--whether that means a potential husband or a natural-health guru. As far as disability goes, she's worse off than me socially, and that's saying something; but she never had the self-care issues that I have, and because she didn't, she's lived on her own all her adult life and concluded from that that she couldn't possibly have any impairment that mattered.
In the end, I think it's society's stereotypes about disability and about autism in particular are what have hurt my family the most. Once the "disabled is tragic and totally incapable" idea hit, it was like toppling the first in a line of dominoes, with the inevitable end result being that I can only be glad that I survived.