Boyfriend vapes I want to quit. Tips?

I can quit cold turkey. I've done it before. I've gone months at a time without vapes but some stupid little part of my brain always wants to try to steal a hit or sneak my boyfriend's vape from him while he's asleep. I don't know what's wrong with me. He knows I genuinely don't want it and tries his best to keep it from me. Whenever I get sucked back in its the first 48 hours I get grumpy and then kinda dizzy/ out of it.

I always regret hitting it when I do sneak it.

I need advice? How do I over come the psychological aspect of it?

My boyfriend thinks I've been off it for at least 2 months now...