Is he just using me?

So me and my friend have been friends for 9 years i met him when i was 13 1/2 and he was 18 and now im 22 and hes 26. I obviously fell inlove with him. Hes been my support when i need someone to talk to. He has also been my first in almost everything. We tried to date back when we were younger, but it didnt work out because my parents were too strict and i couldnt even go out. So we stayed fwb and have been ever since except when I got pregnant at 20 he stopped talking to me for a year and a half because he wanted me to get an abortion and i dont believe in them. Then one day out of no where he comes back asking how im doing and telling me he missed me. We started seeing each other again. He said he wanted to be in my life one way or another, but im tired of only being fwb i want more. Just recently we got into an argument where we both said hurtful things and he stopped talking to me for 3 weeks and it hurt me. He then apologized and things went back as to how they were. He txted me everyday until we hungout again..then he didnt txt me until i txted him. Is he just using me for sex? If he is why keep coming back to me, when he has so many girls throwing themselves at him? And trust me im not the best looking far from it actually.