HiLissa513, and welcome to Psych Central! I am bipolar and I know I can be hard to deal with when I'm having an episode. Plus I think it's hard for our children to see us like that.
I'm sorry your children reject you. Could they be feeling overwhelmed when you are having an episode? And, yes, they do have to set boundaries.
I agree with Miguel's mom's advice. Adult children need to be treated as fellow adults. It's hard to do. (I have two adult children.) But I am trying to keep that in mind. And not impose on them. But I still have my husband, and he's literally been a lifesaver.
Did you and your children as adults once have a good relationship?