Mom issues...

Im not sure where else to post this and I just need some feedback/support...
My mom is diagnosed Bi-Polar and has had struggles with substance abuse.  She's been sober for over a year but the mental illness still kicks in sometimes and makes her very irrational and hard to deal with.  She read too much into a statement I made yesterday and even after having to explain myself she obviously sat there stewing over it because I woke up to a text saying "Don't call or text me anymore.  I am done being the one you all hurt."  I've dealt with these ups and downs with her my entire life but this is really hurting right now.  I don't know how to deal with this rejection from my own mother while I'm over here TTC to be a mother!  I know I can't let her craziness shatter my whole world every time she gets into it, and I usually don't, but this was the longest she had been sane and sober recently and it's just heartbreaking...I don't know how to deal with this when all I want is my mom there for support during this time ?
Thank God I have an amazing MIL that's extremely supportive but it's just  not the same, it's just not MY mom...