Originally Posted by
Zaphod 
I enjoy our sex to every degree, but I feel that my confidence isn't there. My wife goes wild when we make love and she has no complaints in the sex department, but there are just times where I just can't reach orgasm. It frustrates the both of us to a degree that today she cried in my arms and blamed herself for it.
I keep telling her it's not her, it's me.
I would say it's most likely is. The "cumming" in the end is in your mind. The two heads are interconnected.The ability to cum and release is the ability to vizulalize and to submit to your primal urges. This ability can be hampered by anxiety.
Riddle me this Zaphod, do you ever fill anxious during the intercourse which is specific to necessity to cum? Do you feel pressure to cum? Do you feel that not cumming during intercourse is some sort of a failure? Do you concentrate on cumming as the end goal? And then, do you find yourself thinking about cumming over and over again during the intercourse and find that the more you think about it that the harder it gets? If yes, stop right there. You must first find a way to rid yourself off this anxiety. Cumming is not forced, it's not pressured, there is no expectation to do anything that doesn't feel right. How about you stop concentrating on cumming next time you have intercourse. Stop and start whenever you feel like. You don't have to "finish" in any way, shape or form. Just, submit to the motions and enjoy being one in harmony with your partner. Can you do this without feeling anxious, can you eliminate any form of anxiety that's within you? Can you eliminate your necessity to come and with it the fear of not cumming?
If not, I think this is the source of your problem. Perhaps, the next step then will be to find an effective meditation technique, something to clear your mind, relax and feel at peace without any neccesity to succumb to an expectation.