Does my ex mean what he said? I need advice?

Ex boyfriend yelled he never wanted to date me again and cared only as a friend. But three weeks ago he said he still loved me and sounded sad that we were apart. We broke up in Jan but have been seeing each other to see if things could change. I always felt a little uneasy about his actions. Seemed as though he would say he cared but then didn't always show it. But then why would he still contact me so many months after the break up? And during an argument blurt that he would never be with me again? He hung up and I didn't hear from him at all the next day so I blocked his number. I don't plan on speaking with him again. I would just like an opinion as to why guys string along ex girlfriends. If the dislike the girls so much why do they hang on like a safety blanket then all of a sudden disappear???