I am a very horny girl who went several years once without sex so i know where u are coming from. I think just coming out an asking him in a quiet moment would be a good idea. Maybe he is just afraid of disappointing"performance anxiety". I mean he must have been taking care of himself if he hasnt had sex in that long right. I know when i finally got to have sex after a long dry spell I was desperate for it and if your partner is not in the same place as you it can be hard. Expressing your feelings is the most important part. good luck.