My ex boyfriend and I have been broken up for 9 months now and he has a new girlfriend. They have been off and on throughout that time. Every time they got back together I got a text from her number saying it was my ex boyfriend. And I'm pretty sure it was because people who were hanging out with them at the time confirmed it. My question is what would motivate him to text me off his new girlfriends phone?

Wants to hurt you, makes him feel like he has some control

And since you don't merely just delete without reading, or block him if possible, it appears you are reading them and giving them more than 2 seconds concern

He's an ex possibly playing games-ignore him!

I guess you have not replied to his texts. If you have done so, he would have went on talking about what's happening with his life at the moment, and how happy he is with his girlfriend. There can be many reasons he might be doing this, but almost all the reasons lead to the same place called Loser town.

His reasons and motives don't matter not a bit, what matters you ignore them, and him, and don't be drawn back into whatever game he is playing.

He just wants you to think of him, and be confused, so he has leverage for whatever his reasons. Likely to keep you on the string as a safety net. Just in case he needs a safe place. Don't play his game, just be glad he is in the past, and keep it that way.

Pray for the girl, and be glad its not you.