It would seem rash to bounce back and forth between relationships. Yes, he just lost his father and right now, he's in a vulnerable position. If it were me, I'd give that thought a good years amount of space. Right now, seems like addressing the current relationship is priority #1. That was inconsiderate to blow off this weekend, like he did. If he cannot handle confrontation, which not telling you ahead of time about not making it, displays, then that leaves me wondering about his overall character.