By the sounds of it you still have feelings for your ex but he has moved on. 19 years is a long time to be 'off and on' and since you've never quite managed to settle down, now would be the time to let go. There is obviously something stopping this relationship from working.
I understand that you want to say thanks to him, but perhaps this is really just s selfish way of saying 'don't forget me'. After all you are out to 'impress him'. He's not going to forget you. He will always have great memories of you together and you are obviously a big part of his life.
Consider that it may be very awkward for his new partner if you buy him something which really symbolises the love you still have for him. You can't win him over with pretty or thoughtful things any more, but you can give him your friendship.
If you give him your friendship he will never have to remember you because he won't forget, and if you're smart you can both keep it forever.
I understand that you want to say thanks to him, but perhaps this is really just s selfish way of saying 'don't forget me'. After all you are out to 'impress him'. He's not going to forget you. He will always have great memories of you together and you are obviously a big part of his life.
Consider that it may be very awkward for his new partner if you buy him something which really symbolises the love you still have for him. You can't win him over with pretty or thoughtful things any more, but you can give him your friendship.
If you give him your friendship he will never have to remember you because he won't forget, and if you're smart you can both keep it forever.