<human>: Condense the text into a few key points

We have been together for 6 months now and she is the best thing to happen to me. I know she really loves me because anytime she thinks that im upset or annoyed at her she starts to cry and say that she doesnt want to lose me. Enough backstory.

Both our mothers are strict house wives so we cant go to each others house. So sometimes (rarely) as a joke Ill say something like yeah my friend will let us use his place tomorrow but you need to sleep with him or blow him to which she replies with okay or sure if you want. I dont know if shes kidding or not reddit but it makes me a little upset that she would just be so willing. Shes willing to do anything I ask her. Especially sexually. She even does my homework sometimes without me asking. What should I do? Does she mean it? I want to be with her for as long as possible shes the girl of my dreams we even plays games together (League, CS GO, etc) 

Sorry for format and if this type of post doesnt belong here. Just looking for help or advice.
<bot>: joke with gf about having sex with a friend and she agrees makes me feel like she is willing to cheat on me.