There is a great quote one of the members here (Jennifer 1967) has in her signature. It is:

"Don't cling to a mistake just because you sunk so much time into making it."

At the start, you didn't know, but now he has revealed his true self. I know it's hard if you're thinking it's been such an investment, but better now than waiting now that you do know. It will just be more time adding to your regret later. And that's besides the major point others have made about your safety and self-esteem. Wishing strength to you.

(It is advise I have trouble following, but know it is very true.)