1. Seems to always meet him anywhere
No, it's definitely not a coincidence that you two meet each other all the time. He clearly intentionally keeps appearing in certain places to meet you so that you two have reason to continue talking to each other.
2. Ask about you through friends or friends
He is still trying to watch over you. He is still very interested in your life and that is why he asks a lot about you to your friends or friends.
3. Interested in your love life
He seems very interested in your love life. He always asks about who you like. And you can say that he is jealous every time he sees that you have seen another man besides him.
4. He hasn't dated anymore since you broke up
You can feel that he really doesn't forget you if he hasn't yet re-established love with others. He is still dreaming of a day when you two can come back together.
5. Bring up the stories of your past two
He knows that nostalgia is something very powerful and can be used to manipulate someone's feelings. He tries to make you remember all the good times that you have gone through together so that you might later consider the choice to return with him.