In love with two guys

One guy i have been seeing off and on for about a year. He is older and promises once i turn 18 we will be in an official relationship. I have left him more than once feeling like the relationship was going nowhere. Both times i have , I have come back and he has taken me back. I can honestly see a future with him. The other guy, I have known for about three months, And i know he loves me. He is alot more sensitive then the first guy. I have strong feelings for him, although i cant shake the thought that i might make the wrong decision.