I NEED ADVICE!

so i’m 17 and me and my bf have been off and on for about 3 years and i don’t think i wanna be with him anymore. we started dating my sophomore year and thay year i didn’t have the highest self esteem so when he showed me interest i felt like i should talk to him because no one else would show interest. i feel like i’ve been in a relationship my whole high school life that i’m not allowed to leave. i’m the type of person who hates to upset people or hurt anyone. therefore i let people treat me however they please. also he’s currently in college out of state which is very far from where i live. when we’ve broken up it’s like it’s always been on his terms. we break up when he’s ready and get back together when’s he ready. i feel like i’ve never really had a choice in the relationship. he never asks if i wanna be his girlfriend just assume that i want to be in a relationship. me being me i go along with it fearing that i may upset him. when we text he tells me that i’m his only motivation and he was to try and be the best husband he can for me. i’m 17 years old. i’ve never had time to grow on my own and figure out what i personally want. i just feel obligated to be there for him because he’s was there for me when i was going through stuff. he’s alone in a state he’s never been in and id feel so horrible if i caused him to go downhill but i don’t think i’m in love anymore. it’s like i have love for him but not in a future together way. basically i’m asking what should i do. i don’t wanna be with him anymore but i don’t wanna break his heart. please give me advice !!