How can I write a believable male POV?

Men don't usually need to pop out a box of tissues and cry when they get really upset right? But is it to unrealistic for a man to break down and sob at a funeral of someone he really really cared about after seeing said person murdered? I don't know, I don't want my male main character to come off all weepy, can one emotional break down be pardoned? or should I just have him maybe get a little teary and express how he loved the deceased in some other way?