My girlfriend friend

I feel like I'm being irrational. I've been in this relationship for about 2 months (we'll call her Sue). When Sue and I first got together I found out that she got asked to go out with someone else (we'll call him Pete). She declined as she was starting to date me. I've found out that she's still hanging out with this guy on a regular basis and he's constantly texting and facebooking Sue. He also wrote a song about her. And when she first chose me, he sent her a message saying something along the lines of " congratulations, I hope you're happy with your choice, but ill always be here if you change your mind" Now I love Sue very much and I've been told that I'm the first person she's ever loved, but it makes me uncomfortable with this other man (whom I presume is still interested in her) hanging around her all the time. Both of my serious relationships have ended in the past with the girl starting to hang out with another guy and then dumping me for him. I know that she should be aloud to be friend with anyone she wants but it is really weighing on me. I'm not sure what I particularly want to ask/know but does anyone have any advice or similar stories?

I don't have a simular story and altho listening to other stories may help you decide what to do/make you feel better, I also feel that you need to talk to Sue about this. The fear of loosing some body you love is scary, most people in a relationship go thhro these feelings I'm sure. Nobody likes getting hurt or confronting people incase it turns into an argument. But at the same, (if something is going on) time this is unfair on you and you need to know the truth espiacally if its playing on your mind all the time! otherwise it will drive you mad and make you anaylise things more. Yes she is allowed to have male friends but if you feel they are more then just friends (or have been) or something is going on then of course you are allowed to confront/ask her what is going on. I hope this helped