Should I feel jealous about my girl talking to my close friend on her phone and being very friendly?

[rehanQ]

Recently my girlfriend and I were talking and she randomly asked me why my close friend had deleted his account. I didn't know he had so I asked her how she knew and she told me they had talked and now his account is gone. She showed me the conversation and they were being really friendly and frank with each other (they're friends).
Even though I know that my friend has a girlfriend, I felt really weird about it... how should I be feeling?

[Paul09]

You should be feeling maturity. Not sure why you think of this as a negative. Trust is extremely important. You can't do that, then you'll have a whole world of hurt. I'm great friends with my friends wives. None of them are jealous or anything.

[Anonymous]

Its fine as long as they just remain friends, but keep an eye on that situation.

[Zolly99999]

She wants to bang him.