kind of in debate. opinions ?

okay so me and my boyfriend have been together for awhile. before we started dating we were best of friends and he’d flirt with me. and once we go together we were so close and his energy was great. and he was putting in so much effort. i just don’t feel it anymore. like when i text he always responds with “k, or idk, yeah” like he’s so nonchalant. and i hate it. i know everyone will be like just leave. but it’s just i love the boy to death. i’m kind of torn , i keep getting bad thoughts of this ain’t what i want. but then again i’d be horrified if i left and just the thought of it i hate. i tried to address the problem with him and he said he was sorry etc. but nothing has changed. he doesn’t seems to care anymore. and i tell him he never talks or makes conversation and he says he’s always been like that. like it’s not him. but that’s not true. and whenever we hangout he’s just always off. he’s not as touchy , never wants to cuddle. he never wants to go out and do things. he always wants to sleep when he’s over. opinions ?