First, and most importantly... my condolences on the loss of your Mum. I'm sorry.
I think you are very right, this isn't a good time to make decisions. It might not be a terrible thing to give him small opportunities to support you as you go through this, maybe it would give you a little window into who he is now.
I believe it's a good thing that you are now the one that can decide what direction things will go. There's no rush, in any case. "I don't know." is a perfectly good answer, for now.
