There is some evidence that hormone levels have an effect on how intensely men and women feel emotions. High androgen/low estrogen (relative to levels of the same hormone, not to each other) levels tend to increase aggression and libido and decrease the overall intensity of both positive and negative emotions, while the opposite is true of relatively low androgen/high estrogen levels. So it is in part affected by sex.
Societal, familial, and other social influences probably play a much bigger role. "I hate to see a grown man cry" was a standard saying at one time, and crying is still in some circles seen as a sign of weakness/feminine behavior. This is changing, but there is still some built in societal bias that says that there's something wrong with a man crying in public or in front of others, and many boys are routinely taught that crying is an inappropriate response, that they need to "be a man", a phrase I'm not very fond of in this context. Interestingly, it's changing in both directions--there's more disapproval of women crying and a little less of men doing so, provided it's in circumstances that OK for men to cry.
I'm a crier, and not the least bit ashamed of it. I wasn't, not for a long time, because I tended to tie any strong emotions up inside myself to keep from being consumed by what my life was like most of the latter half of my childhood. The problem was that by tying up all those difficult, negative emotions, by suppressing those, I was suppressing everything--all the good stuff went down into the dungeon I built for the bad stuff along with it. It took a lot of time and practice and help from others, Grace, Sissy, and two therapists to help me regain access to all those things, and to understand that it's OK to feel strongly, that the sadness and the joy are a part of the same thing--you can't have one without the other. Now I'll cry at movies, books, when talking to Grace or my therapist, any very strong emotion can bring tears. It's not always the big wracking sobs, and I've learned how to deal with it, to let it come when it needs to come, to put it away until later when I need to, and I deal with it much better than I did, in a much more healthy way. I still have some balancing to go in how I deal internally with certain emotions, but I've got a good grasp on expressing them in a healthy way.
My wife very seldom cries. I can recall maybe . . . three, four times. The last time was the first time I was conscious and sane after my accident last year. My sister says she was calm and controlled when I was in a coma and during the times when I was incoherent, but just let go when I finally recovered and was me, the person she knew again.
She's never once gotten upset with me for being emotional, and it doesn't bother me that she isn't more demonstrative in how she feels things. It did take a bit of time to learn to read her, to see that just because she isn't more obvious about how she feels doesn't mean she isn't capable of intense emotion, she's just a little more self-contained than most people. In fact, that she reserves that stuff for private times with me makes it something a bit more special for me.
And I so tell the man I'm with about the other life I lived
And I say now you're top gun, I have lost and you have won
And he says, "Oh no, no, can't you see
When I was a girl, my mom and I we always talked
And I picked flowers everywhere that I walked.
And I could always cry, now even when I'm alone I seldom do
And I have lost some kindness
But I was a girl too.
And you were just like me, and I was just like you
from
"When I Was a Boy" by Dar Williams