Crying is a natural mechanism to relieve built up stress. Sometimes, when I know I need to cry (i.e. the awful arguments I've been having with my mom the last two weeks) I'll deliberately play sad music. It helps me to relieve the tension that is built up in my chest and the rest of my body. It also helps heal the heart by relieving pressure. You can literally die from heart break (seriously, look it up), and bottling it up only makes it worse.
So, it's a very good thing to cry. Perfectly natural, and when you have to, find a way to force it.
I hug my Snowdrop. She's so cuddly with her minky fur and her cotton mane... :3