Can someone please explain vengeance and doomed love IN Hamlet (Shakespear)?

Hamlet could have said something like: Yes, this whole death of my father and my mother's marrying him so soon is a little bothersome, but Ophelia loves me and I am next in line to the throne. I'll watch my back, but I think I'll work within the system. But he doesn't, and in fact makes a bad situation very much worse in seeking vengeance for what is after all a ghost.