For whatever it's worth, I'm thinking about my ex
I'm wondering what that might be about.
He's no longer in my life but I just can't stop.
It's okay to not forget about old relationships completely.  As long as you are not obsessed with your ex, then it's fine to think about him from time to time.
I still want to be with him. I wish I was still in his life.
Ending a relationship is difficult and feelings do not go away. Just take your time and try to move on on your own pace.