Advice?

My SO brings up his ex he was with for 5 years all of the time. They had a house together, money, and they were highschool sweethearts. Everytime we get in a fight he brings her up. The reason why they broke up is because she got on the depo shot and it made her to where you couldn't even be around her anymore. Then he met me. I have no job, a sucky family, and I'm nothing. She had a rich family, she was older. The ONLY reason why they broke up was because of the shot. Does he still love her? I cry almost every night thinking I'm nothing and that he can do so much better. I need advice.