Boyfriend help?

I love going up my friend Paula's house, she lives 20 minutes away from me. My cousin also loves going up to the same place but she dosnt hang out with Paula. Anyway, I met this guy up there named David, who my cousin went out with before and she dumped him. I've been going up the same place hanging out with Paula and David and his friends. The other day he told me that he loves me, and i almost cried. Yesterday I went up there to see him and he asked me to give him a hug, i was wishing that last night would never end. The problem with this is that my cousin i find is still in love with David and hangs around with his sister. She always goes up to see him and his sister, but sometimes my mom wont drive me so i have to find a drive and I only can get there on weekends. I love david soo much!! But since my cousin goes up there all the time, and I don't, im scared that David will not love me anymore and go out with my cousin.What can i do?i no its a free country but im still scared. help