Why does he want to bait me or make me upset about the fact he is dating another girl?

Anonymous
He was flirtatious, teased me a lot and sometimes still does, every time I saw him he would stare, he would eavesdrop when I would talk to others and still does. Even when he first started dating her he would say suggestive things to me, flirt, tease etc. and even stroked my hand in the elevator in front of her (although she did not see). A week later when I told him to keep his distance due to his ambiguous bullshit he came up and said something very cruel to me but he also told me we were just friends and he didn’t want to hurt me (although 10 mins later he was telling me my life was shit). We patched things up as friends slightly due to my efforts but even after all of this he would still stare intensely, tease me, etc. Then one night at my friends birthday he said in front of the girlfriend that “dating her was a white lie” and he winked at me. I told him later that was really unkind. To her and to me really. Anyway in spite of everything he makes comments about her and he knows he’s made me cry at least 3 times in the past and he’ll put emojis like 🥲 in groupchats and well he’s clearly trying to get under my skin about the whole situation.. why? Why?
Why does he want to bait me or make me upset about the fact he is dating another girl?
2 Opinion