When I'm not in mood to have sex with my bf I'm open to telling him 'No I don't want to have sex babe' but he gets so upset. I try to comfort his ego afterwards but he still feels frustrated and rejected anyway. There are many reasons why I don't want to have sex at that very moment but he just doesn't understand and becomes so upset.
example:* My mind is preoccupied and can't focus while I'm having sex
*I don't want to have sex when he's been out or on his fames all night and then comes me as though I'm the last thing on his mind
*I'm tried
*I'm just not in the mood to have sex

This morning I felt he was lecturing me and it didn't make me feel good. Now I'm worried that every time I want to tell him 'no' I'll have to prepare to be lectured at. We have sex at least every two or three days so it's not like sex is non-existence. Many times I'll explain why I don't want to have sex hoping that it'll help him understand why I'm not in the mood so I don't leave him dumbfounded why I don't want to have sex.

It is frustrating when he doesn't understand why I don't want to have sex. I wish he wouldn't get so upset. Does anyone have experienced this before in a relationship and how have you dealt with it? Please send advices my way on how to communicate with him better.