You need to try a bridging technique where you take the orgasm from one situation and bring it into the intercourse situation. This is not really complex, but does take a little professional intervention. A sex therapist can help you. If there is a sexual incompatibility now, it could get worse. If she is feeling guilty about having sex out of wedlock, she could feel more comfortable having sex after marriage.
Age has a very mild correlation with a good orgasm.
One of the requirements of orgasm is the contraction of muscular tissue. If you regularly have sex, then you can have super orgasms in your 80s. If you have long periods of no sex and don't exercise these muscles as much, then your orgasms won't be as great. He says he's afraid he will feel too much. Either he is telling the truth or he is lying.