what do you do ...

when someone is in love with you and they say this has to work or it's it for them.. like yes suicide i make them this happy that without me they can't feel happy or anything. And then the other person who is in love with me has been my best friend/on and off boyfriend for 6 years. I have no clue how to break it to the first guy that i'm just not over my ex and i have told him before but it's like hard for me to fully open up. I need advice i know either way someone is getting hurt but my heart longs for my best friend. I definitely need to have space and be alone from men in general but i don't know how to go about it.