Happy relationship happy life ..is it possible?

so ive dated this guy for 4 months and we love each other so much ive never felt like this before he is so special to me he took me on my first date he was my first kiss my first make out he took me to my first rodeo he is perfect he plays highschool football and ive never dated a guy like this its a dream come true and im afraid to get any closer becuase ive gotten hurt by guys so many times its like i prepare myself for the goodbye or ill hurt them so they break up with me just beaucse im use to it ...but i am so not doing that to this perfect person i love so how how do i keep it where it is i love where were going we always wanted to get married have 3 kids and live forever together so i dont wanna hurt him i dont wanna do anything to harm him how do i stay where i am ...i dont want to ruin what i got now please thanks