My mom constantly judges me for having sex?

I'm 20 years old, from a pretty strict catholic family. My parents are very old fashioned and believe you should only have sex when married. They both waited. Although some might think it's a good idea, I just think the idea is old fashioned and a little unrealistic. Maybe that was the thing to do 30 years ago but in this day and age I feel like hardly anyone waits anymore. She was furious when she found out I lost it at 17 and lectured me about it forever. She calls me bad names and thinks I'm easy for having sex with someone I love. I came home drunk one night and my birth control fell out of my pocket. She was disgusted and called me a skank. I thought I was being responsible for putting myself on it but I guess not. Everytime I go out with a guy she accuses me of having sex with them and saying they are using me and they will leave me once they get sex. I respect her for waiting, but it's my life not hers, and I'm an adult so I can make my own decisions. How do I just get her to accept it though and move on and stop judging me?