Marine Boyfriend Cheating??

So ladies I have a long distance boyfriend. He’s a marine and he is the sweetest and most loyal guy I’ve ever met. But everyone keeps putting our relationship down and talking crap saying that cause he is a marines he’s going to cheat on me or he is cheating me. My friends keep saying he’s going to bars with a bunch of chicks. To be honest it’s getting in my head and I just told him how I felt and I’m scared he’s gonna be upset and mad at me idk what to do ladies. Can y’all give me advice on how to deal with this??😩🤔