I'm in the military and me and my girl share phone sex when I'm away. Just recently we tried phone sex. She got in a doggy style position a her vagina began farting before she could master bate. Does this mean she had recently had sex?
No it does not!! It happens. The vajajay is flexible and there are many places for air to get trapped. It can happen just in how she sits. Or happen just as she was getting in position for u. If she's had children it happens even easier.
Please be the strong man that u r. don't assume she screwing around u all the time. Don't go looking for things that aren't happening. U will make urself and her crazy.
Don't demand that she prove it to u, by asking her to do demoralizing things just to build up ur self esteem.
History and my age tells me, the one who is feelings by insecure about it is the one that is cheating. Not always. But most of the time. The accuser is the loser. Either get out of this relationship while u r away or get some emo support from a qualified councilor. Not ur buddies.
Be good to ur girl. The 2 of u should only be in a relationship if u r building each other up. Not tearing each other down and looking for faults that may not be there.