My partner cannot achieve orgasm and I have lost all confidence in bed

We love each other, but I feel the problem is down to my poor performance although he assures me this is not the case,I have been reading about men not reaching orgasm during sexual intercourse. I am at a bit of a loss as to how to deal with this. I have been with my partner a long time, and this has always been difficult for me. I am as uncomfortable with it as he is. I have reached a stage where I have lost confidence in bed and feel it is all down to my poor performance, but he says he enjoys