Hi Bambi, welcome
I dont know any groups, hoping someone can post some, I'll put the wor dout among other community champions.
I'm sorry to hear of those sad event, some of us here have been in your situation. My brother and uncle went that way. Also my sister and I (and likely my brother) all had/have bipolar. So my sister and I attempted in the past.
Now, the information I can pass on to you is this grieving period will slow and settle over time and time is the only real healer, but groups can suit some people, after all the actions dont make sense to many people and that lack of understanding needs to be pursued so you can move on...albeit eventually.
It is a tough time and a time when family need to stick together. I have no other words but to wish you all the best.