Absolutely, there is no "right" way to act or an externally imposed standard of behviour to meet. You're hurting and it's just fine to be angry. It's honest. Working through it can sometimes involve remembering that anger is rooted in fear. The fear that the relationship you once relied upon might be over, the fear that he might not come back, the fear that his feelings have changed. These are profound fears and it is natural you would be angry as a result. Being honest about your fears, anger, and hurting is not weakness!
I wish I could offer you some comfort in the way of assurances, but the uncertainty is part of the gig. I can offer you my goodwill to hear you and not to judge and to support you to the extent that postings to a forum board allow.
Female, Friends & Family Forum Fan