Girlfriend seems like she's losing interest in sex life

I have been with my girlfriend for 2 and half years. The sex and 4 play use to b awesome. Latley its been a drag and so rare for it to happen. She gives me oral a lot but I get turned down like everytime when I want to make her feel good. I went down...

on her a lot in the past but latly she doesn't want it at all. im getting worried if she losing interested or if there is some sneaking around. we hang out together everyday and have sleep overs basically every nite. And sex, it doesn't seem to last long any more. She says it hurts but I doubt that cause my penis didn't grow. I hope I get some feedback from both males and femailes on what is going on. I really hope this isn't a hint of us breaking up. I love her and she tells me many times everyday she loves me. Please im going crazy over here. Can everyone help please. Thanks everyone for your time

I cant really speak on the whole matter bc I dont know bout that.
But I know speaking is very important in a relationship. So why dont you try and talk to her about it and tell her what your thinking and how you feel. Shes the only one who can tell you for sure what is going on.

well um maybe you should try doing something new to pleasure her...
maybe shes getting bored with the regular techniques