What would you do if an ex (M29) texts you (F26) every year ? (Asking on another group even if I know the answer)

Years ago I have dated a guy who was lovebombing me at first. He was literally running after me, even when I did not expect him to help or else. Then he focused on looking for a work and it was taugh. He was absent and I felt invisible. I was investing in someone who was dealing with emotional issues (or feeling lost) and who wasn't investing and treating me bad. People knew. He flirted around, drank. He said I am special and another time that he could not offer me what I was looking for. He wasn't ready. He was acting hot & cold. Months later, he texted me asking for news and put me on view. A year later he visited my country, our friends. Month after he stalked me. He followed me back several times before unfollowing cause I did not follow back. Week later he texted me elwhere. He wanted to catch up on a call. Ive asked why as it's been a while. He never answered.I have heard he has drinking issues and often parties. What behavior can you see there, should I block ?