my mom got divorced after she remarried too - they had a good reason, but i hated it at the time even though my biological dad has never left me. it was hard for a while, but i promise you it gets easier!
It’s possible that their separation, and both being in healthier places in their own right, could help them to be able to support you more fully too. You don’t have to lose anyone. I hope it works out for you, OP.