Maybe it's just me, but I believe that people deserve second chances. Everyone is capable of making mistakes, of letting emotion cloud their judgement and acting selfishly and sometimes blindly due to being hurt or angry. I've seen it often enough to know that once that has been exhausted, and when people really have the time to just think about things rationally... well, their stance and attitude can soften.
I know how badly it must have hurt you. And that's something which no doubt will take a very long time to get over (if you ever actually can). But personally, I find it helpful to try and put myself in someone else's place and try to think about why they act the way they do, or say the things they do. Where it comes from, you know? Your mom may be a lot of things - insensitive, maybe selfish, tactless... whatever adjectives you care to use. But maybe she's also scared, and sad, and creating defense mechanisms to help her cope with all the feelings she experienced when you came out to her. I mean if you think about it, it was just as much a big thing for her as it was for you.
I'm not excusing what she did, but what I am saying is that however irrational her words and actions, they were based on very real feelings. Feelings that she may be starting to overcome now some time has passed, and that she perhaps realises that no matter what she tries to get you to change your mind, you aren't going to be dissuaded from your course of action. Maybe she's realised that the parental bond is one she still feels. I don't know. But I feel that if ever an opportunity presents itself, then it's preferable to build bridges rather than burn them.
At the very least, you have nothing to lose, and everything to gain by hearing her out and maybe having a calm, adult, rational conversation about the way you both feel. Who knows, you may each learn something about the other in the process.
