Helping out my exes

I have three ex girlfriends who continue to call me and ask me to hang out with them. I am faithful to my current gf and being faithful is something that I take pride in.

Two of my three exes told me they currently have boyfriends yet they still continue to call me. My gf is aware of this because I don't hide things from her and the exes have called me when my gf was with me. Sometimes she gets annoyed and at other times she gets a bit jealous (kind of like a healthy dose of jealousy).

I don't mind being cordial with my exes and giving them good advice like telling them to keep their chin up but it just seems wrong how they call and ask me to go out with them when they are in relationships.

Well, you don't have to go out with them when they call, do you? Just tell them you are busy doing something with your girlfriend.