I'm having boy troubles?

Okay, so I'm 14 years old...There's this boy that I've known for a little over a year, and I REALLY like him. He's 15. Originally, he asked out my best friend, but it just didn't work out. Itook him to my church one day, and he got saved. Ever since then, we have been the best of friends, and he is over ALL THE TIME! He really likes me, and I really like him, but we have decided to wait on dating because we want to be mature when we do so we don't screw up our relationship. He's not your typical boy because he is naturally very sweet and gentle, but he does lie to me a lot about stupid things. Two days ago, my friend's ex started texing me a lot. He did want me to send him inappropriate pictures (which I did not) and do things that almost all boys want to do at 14 (which I will not.) He said that he loved me, but also told me that I could lose a few. The other boy told me that I ws beatiful and perfect just the way I am.Which one should I pick? How do I severe the relationship with the one I do not want?