I would say, we can work on controlling meltdowns, and how we react to that, quite a few people here have adapted healthier ways of dealing when they hit that point.
That said, I personally would not remain with someone with an attitude like that, alongside the fact, it is not a sickness. It is a neurological deficit.
Unless she simply worded it wrongly, and was referring only to the way you behave during meltdowns, and I would ask, what is it you do during meltdowns that have made her say this in the first place? do you break things? do you scream and yell? In which case, I could understand her having become upset, as when I have done those things, it has caused a very bad reaction in others, who simply do not have a clue how to deal with such things, anymore than those of us with an ASD can deal with certain oddities of the NT world.
However, if she meant that unless you get rid of the Aspergers, she doesn't want you back, then I would simply walk away and be done with it as you have done. Are you diagnosed? If not, is it possible she doesn't believe you have a condition that can explain the way you are?