Jay, you're probably right.. :/
First off, I hope it works out for you. Perhaps she will change her mind, try talking to her. You probably did like her more than you thought, did she give any reasons for why she broke up with you?
Maybe you should ask for an explanation, or just ask to talk it over.
Trust me, you did not like her if you made the decision to "like" her only. It's common, and will make an illusion within your feelings that you did indeed like her. But in reality you do not anymore than you did before. It's just that you're feeling envious that someone else will be with her now and not you. My advice is to think of who your future is going to be instead of rummaging in the past.
I know its not manly, or macho, but EVERYONE has to cry. Every now and then I feel all the crap I've kept bottled up start to overflow. Just letting it out and crying, hard, will life a huge weight off your shoulder.