Susanne - very good advice here - can't add to it.
We have bipolar in our family. 2 generations. So have experienced some of those problems. Especially with our younger son.
With the help of professionals, and his connection with a religious group he has 'got a grip'. He's 53 now.
He has the advantage (?) of being very bright intellectually.
Also diagnosed as having Asperger's syndrome.
I don't know, he's still my G...... We have many interests in common, especially music.
Don't give up.
Last weekend, in Rutland, the first statue in Britain of the late Elizabeth II was unveiled.