@Jamjam1982,
No you're not stupid and no one is suggesting that you are.
I bought my ex a motor bike, should have seen the look on his face, no one had ever, ever ,done that before.
After 2 months he wanted to trade it in and up-grade it? Use my money as the trade in, yep, cost $5k, give me $2.5 he did.
Otherwise he would have "taken" and sweet? He is possibly all about his child and will do ANYTHING for that child.
But here is the difference, if he was ready to move on, start a fresh, he would never, ever, ever, forget your birthday. He didn't forget hers.
Do not allow yourself to be used.
Keep the car and kick him to the curb.