Ask Dan & Jennifer

OK, first off let me say I don't believe there is anything wrong with the age difference (my fiancee is actually 22 years older than me). However, that is only the case when there is a relationship. This sounds like he's using you. But apparently not for sex, since you say you've only had sex once in three years.
Sex shouldn't be what a relationship is solely based on, but for most people it is quite important. If one partner wants it, and the other doesn't, it can create quite a rift in the relationship.
Now, I'd like to ask you, what does he do for you? You say he doesn't give you sexual gratification, and he stands you up. So why do you want to be with him?

Any relationship cannot be 1 sided. Both partners have to give and take, one cannot be always giving and the other always taking.

Based on what little info you've posted, I'd say examine the relationship, and if he's taking and never giving, then find someone new.