Why does my ex always lie to me?

Basically me and my ex broke up two months ago due to arguing too much. We decided to stay friends.. but had a few arguments.. anyway, he asked he meet me for a drink, and was saying how much he misses me, then the next day he has a girlfriend and started being rude and nasty towards me. Is it because he still has feelings but knows we won't work so he goes for the first girl he sees. Plus he said to me he wants to move away, (we live in southampton) and funny enough his girlfriend lives in winchester.. so its like he's using her to get away.
Anyway one minute he said he still wants to talk, and now he said he doesn't want contact.
Yet he hasn't blocked me on facebook? Is he just keeping an eye on me whilst being with his new girlfriend?
He loves treating me like crap thats for sure, but he's my first love, and its difficult.
Why does my ex always lie to me?
Add Opinion