Bipolar episodes can and do happen randomly without influence from the environment.

At the same time, life situations can trigger episodes as well. They can also make an episode better or worse, just like situations would affect you when not in an episode.

Yes, you will be different when around different people - just like you would be when you're not depressed or (hypo)manic. No one reacts the same to everyone they know, so why would it be different when ill?!

Everyone experiences things different, so the age of onset is not consistent. Personally, I first had problems with feelin suicidal at age 11.

I take responsibility for my actions and how I treat people, whether I am in an episode or not. It's still me and something I've done.