Hi Samantha,
It used to be so hard for me to express emotions. It wasn't until I went to individual and group therapy in my thirties that enough of the frozen inside was allowed to express itsself. When I was in group, I began to cry so hard, it started scaring the other group members, but oh was it ever so good to finally let all that stuff out. Since then, it doesn't take much for a movie or incident that I can relate to, to start to cause me to ball my eyes out. So much of it comes from childhood repression. I never want to lose the ability to express myself emotionaly again.
Just learn to be OK with yourself, whether you feel like cyring or not. It will come in time. The irony is that the more you are OK with yourself as is, even with not being able to express your emotions as you would like, the easier and sooner they will come.
My wife and I have often talked about how we both have to play the "strong one" to others in our lives. And where do the strong go when they need to turn to someone? - to each other!