I have been with my boyfriend for three years and have not been with anyone else since but last night during sex he said that he couldn't feel it and he now thinks I am cheating on him do you know why it could just feel looser for no reason could it have something to do with my period just ending? Please help he wants to break up over this.

During different times of the month a women's body is different. I find that right after my period, things a slightly loser too. Also, depending on your age, your hormones could be acting crazy too.

I would be concered that after 3 years he doesn't trust you enough to believe you. I would wonder what he is hiding.

That was my first reaction.

Many things can make different sensations. Things to concider are lubrication (the wetter it is the looser it feels), how often you have sex (the more often you do it, the looser it gets), how hard his erection is (that can vary and obviously will make a difference), how far your cervix retracts (this happens the more excited you get), your position (some positions will spread the surrounding bones and tissue more then others), and also if you have used any adult toys that may have been larger then he is.

I would also be concerned that he is acting out because he is feeling guilty about something. Men have a tendency to play these reverse psychology games when they have been bad. You know, redirect the attention to you. Of course, none of us would know if that is the case, but it's something to concider.