Is the relationship worth it?

My fiancee and i have been together for 2 years. I am 22, he is 32. We never have sex anymore. He blames his age, claiming he is alway tired. I know he masturbates everyday in the shower (he told me this).. He said the problem is that i never initiate sex.. i used to initiate a lot, but he'd always reject me.. saying he was tired, or not feeling well. So i've given up.. i'm too young to be in a sexless relationship.. i'm 22 and have a high sex drive. Should i even bother with this or just move on?