I just shed a tear for you. I think you need to give it some time right now. The loss of your father is more important. If your bf wants to be there for you though maybe you should let him. After you've had some time to where it won't kill you maybe you should ask your bf WHY. Hearing why he wanted to see other people could help your relationship. Maybe there is something that was lacking that needs some fixing. Maybe it's nothing that has to do with you at all. Maybe he isn't ready to be with one person and commit?

Either way, you should find out why. It will tell you whether or not you should be with him.

Just my opinion... that's what I would do.