"... because they(men) can not handle negative emotions and rejection as well as women."
And this is not by nature but by nurture. Men are generally less emotionally developed and skilled at handling emotions because culturally men were taught to suppress them. So yes, therefore males statistically suck at dealing with heavy emotions. I've spoken with many intelligent young men in their hardships and it really did surprise me how could they be smart in some practical manner but held medieval time views about how to handle emotions. The metaphor the best described it would be just stacking dynamite next to a fireplace and getting dismissive and aggressive when asked about it.
Throw in some good 'ol "My value as a person is how good of a provider I am" or some other fun shit and yes... men are dropping like flies because no one taught them how to handle it correctly and very few learn it on their own.
We were raised in Finland so none of us were taught to have any emotions, show any emotions and definitely not how to deal with them :D More on that later, with @escapist and some very legit personality tests :P
Are you sure you're not using some kind of female centric standard to measure men's handling of emotions? If men, as a group, really sucked at handling their emotions, they would be a sorry dysfunctional lot and not the builders and maintainers of civilization they are. When it comes to men committing suicide more frequently than women or developing a drinking problem, you should remember that men's life outcomes are more diverse in every way than women's.