i need help regarding my bf.

so i recently got with my bf, he's nice and all, but i felt forced to like him back and i dug myself into a deep deep hole.....every "i love you" "i miss you" that i tell to him feels so forced and un genuine, and i do recognize that i should've just let the guy know that i didn't want to date at all really. everything i talk to him about or tell him about are things i think he likes to hear and i do know its bad because im technically leading him on, i didn't have any intention to do so whatsoever. i want to end things before we get too far into our relationship, but i don't know how to do it without it resulting in him getting hurt. he's severely depressed and has told me previously that he has attempted to commit multiple times, that he's looking for a reason to live and that i'm his reason to live, i don't want to be responsible for someones death, but i also don't want to stay with him at all. he gets upset some what easily and all of my memories of us talking has always been sexual, i don't know how to put my foot down and say no, and i feel so ashamed of it.