It sounds like you'll be facing at least three rather unrelated challenges:
- sharing a domicile,
- dealing with bipolar, or its remnants,
- learning to live polyamorously, up close and personal.
Any one of those things could be a make-or-break challenge all by itself, so combine all three and things could get pretty complicated. So yes if you can figure out any way to get separate domiciles, do so.
In the meantime, check out our Golden Nuggets board
to help get yourself up to speed on major poly issues. Explore this site in general, as much as you can. Post your thoughts and questions to get additional feedback.
I hope all goes well, and that Polyamory.com can help.