help?

okay guys I need advise. me and my bf have been together 3 years and recently he just wants to smoke weed only of a night time when were chilling in bed but we just don't have a sex life anymore? If I didn't have a vibrator I would be climbing the walls lol. at first it was amazing and now our sex life is non existing! literally only have sex when it's been about 2 weeks (probs cos he hasnt hadn it in a while) anyone else have a lazy bf? am I being paranoid/ selfish or do I have reason to be annoyed?