Why is he being like this?

Long story short, ex got mad didn't talk to me for 6 weeks, when we finally did talk he said he lost feelings in that time and still cared about me, he said he met someone else and didn't want to work things out, and he really liked this new girl. He was going Back and forth saying he did have feelings for me, then he didn't, he was confused and didn't to now what he wanted. I was upset so I stopped trying, I didn't text or call. After 5 days of me not contacting him he texted me to come over and talk. He said he still wanted to be friends, he still cared and wanted to text and hang out. He also told me it's not what I think with this girl, she has a fiancé and that's all she talks about and he's had his fill of it. We texted for a few days as friends, we didn't talk about us or her, we hadn't talked for about 5 days so I texted him hi, and he never replied, I've called him once. So now he's ignoring me again and I don't know why. I'm angry about it, a little sad but confused as to why he's ignoring me again. When I went to visit him, his looks and the stuff he was saying have me the impression that he still had feelings. Any advice? How to stay strong and not contact him? We were together a year and a half, we've know each other 3 years.