Can some one explain?

hi, i was with my ex boyfriend for 6 years and we split cos he thought there was something missing between us, he kept in contact with me cos he wanted to see my dog, we ended up back together as we were walking the dog together we split again same thing, he took the dog out often, then he invited me out with him (again) and we got back after a couple of weeks we then split again!!! i love this bloke dearly, we did not talk for 6 months then he got back in contact i ignored him but whilst i was walking my dog i bumped into him and we ended up going out once a week as friends, well it got to point where i coundn't handle this so i sent him an e mail saying not to contact me, he said i can always contact him at any time, i know he ll contact again i'm just sooo messed up thanks in advance