Okayy , i have this boyfriendd , hes a major sweet heart but i think im still in love with this other guy /?

Ive known this other guy since i was like 5 , we have always got along very well , and we have always flirted with each other , and we care deeply for each other also . But after i started to quit hanging out with him i met this other guy and he loves me so much , and he would do anything for me , i dont think i could hurt his feelings , but i honestly dont think im IN LOVE with him . Now that i have started to talk to that other guy i am realizing how much i truly love him , i really dont kow what to do , i wanna follow my heart but i dont wanna break my boyfriends .