Sorry if that question is worded strangely, but I have a bit of a situation on my hands and would like some no-nonsense advice from you ladies here.

I dated a man for seven months starting in January of this year. It was...not terrible. No huge fights, no cheating, no major disrespect. However, by month five, he was basically just doing nothing for or with me. When we spent time together, it was us cooking a quick dinner and then working on our respective laptops side by side. We no longer went to museums, galleries, restaurants, heck, anything. When we were together, I had to carry the conversation so hard my back was about to break. The spark was just gone. We went on a summer vacation together that was just mind-numbingly boring, and that solidified my decision: I broke up with him in late August, so three months ago.

The breakup was basically just like the relationship. Amicable, no shouting, nothing out of the ordinary, no huge feelings. I was ready to consign him to a footnote of my year. I cried a bit for a week or two and was perfectly fine afterwards, and I assumed he would react the same way.

However, he hasn't.

The first few weeks after our breakup, he was on a work assignment in a different city. Accordingly, he had no contact with anyone here.

We share some acquaintances in common. Since he has returned to our city, these acquaintances have reported back to me that whenever they meet him, he will go on for hours about how much he misses me. He claims to drink daily. He cries in front of them, sometimes in public. He begs them to transmit messages and give them advice on how to 'win me back'. They are all concerned, more for me than him, because they all uniformly report to me that his behaviour does not seem stable.

I'm honestly just flabberghasted by this behaviour. This was not a man who EVER gave me the impression of valueing our relationship enough to cry for it in public. I know better than to be flattered, I'm just completely dumbfounded and don't really know how to deal with it.

He is not harassing me directly. We have absolutely no contact. I've instructed all common friends not to share any information about me under any circumstances, but due to the exingencies of my job, it's pretty easy to find a lot about me on google. Other than that, I just don't know how to deal with this- I feel somewhat concerned, because a grown man is out there crying to half-strangers in public about me, and that just seems unhinged. But I just don't know how to react in such a situation.

Any advice?