Do you feel guilty pleasuring yourself or is it something you think is dirty?  Honestly it is something children start to do years before puberty.  If you are not able to achieve orgasm by yourself you probably won't be able to achieve it with a partner.  Some women I have been with have said they felt like they were going to pee when they climaxed causing some apprehension continuing.  Over time we were able to work that out.  If you have similar problems be sure to go to the bathroom before you have sex.

Do you have meaningful relationships with your partners or are they casual acquantances?  A quicky might be quite satisfyng for many people it is often more difficult to climax due to the lack of intimacy. 

If these are boyfriends do you take the time together to know what each other likes, how long, how hard or how fast?  Are you talking with your partner during or after sex to learn what each of you liked and what worked?  Did they use that information next time at the mound to hit you a home run?

Not everybody likes to talk during sex and most men and women don't want to give directions.  We all like to be taken care of and when it comes to sex we all kind of expect or hope our partners to be able to just rock our boats.  Still alittle fedback goes along way.  Don't take it for granted that he knows what you want.  A gentle nudge to keep him where you want him, a tug on his hair, a little acoustic feedback, (grunts, groans and screams or other noises to exemplify how you feel) while he is trying to satisfy you will let him know if he is getting close.

Making love to your boy friend is special because you are not just getting off.  You are able to spend the time to really enjoy each others pleasure in what you are doing.  You being to get much more satisfaction from your partners fulfillment.