I have only.ever witnessed one manic episode in a lady that I think is one of the nicest people I know. It was confusing at the time, she jumped around rearranging furniture (in a public place) and accusing everyone in the room of failing to visit her when she was depressed. It's not the same as living with someone who has the diorder, but I still really like her and she was nice when I met her the next time.

From experience of living with someone who refuses to get help for a different disorder, I feel that the hard part is trying to figure out if their behavior is who they are or if their mental illness is a separate thing that you can't use as an indication of their character. It is a good sign that your boyfriend accepts the diagnosis and is willing to have treatment, but those bad times will almost certainly come again.

It is hard not to take things personally even when you know someone's insults or aggression comes from mentsl illness. I hope you are more resilient than I am. My family member can get so nasty sometimes that I panic and don't know what to do. Then they will suddenly act nice and it makes me think I might have overreacted or I that I am losing my mind.

The best thing you can do is try to have a good support system and take time for yourself when you need it. Maybe decide in advance an activity that will help you destress and relax that you can turn to whenever you feel overwhelmed.