I'm going to text an ex on our birthday in front of my current girlfriend
Why would you text your ex in front of your gf?
Yes, I've been thinking I want to meet up with him.
Is this to make your current partner jealous? You should not use your ex to make your current boyfriend jealous.
I tried to, but it didn't work.
I really don't see why you think how this is okay to do. I feel as if you should apologize to your partner and never try to make them jealous again.