Ex Gf

I think my ex gf wanted an alpha male, which is most certainly not me. She constantly talked about how great it would be to be with someone dominant and manly. Towards the end of the relationship, she talked about getting a vibrator because the sex wasn't great. She never cuckolded me (that I know of) but other guys were into her constantly and she made sure I knew that.
In the end, I broke up with her. Since then, though, I've gained a lot of weight and am still single. She on the other hand lost weight and is in a new relationship with a more alpha guy. We don't really see each other, but I know she would really rub it in given the chance.
Do I deserve to be jealous? And did my beta-male qualities frustrate her? Does she even think about this? I don't know. Part of me wants to know about her life via Facebook. Is that wrong, or do I deserve that envy too?