When is it ok to just tell this man to jog on?

[Utrecht]

Dithered about putting this just in chat... Maybe should have but it feels like classic male/female socialization so I'm here instead. Would appreciate any thoughts...

There is a man I used to work with, two decades ago when I was a recent graduate. We worked together in the same department for about a year. He's about a decade older than me, we had no particular friendship but did socialise out of work as a group - after work drinks, the odd bbq, nothing else.

Over ten years ago, after about ten years with no contact at all, I got an email from him - sent to a group, not just to me - saying that he was about to kill himself and that 'the fact this will mean nothing to you is one of the reasons I am doing this.' I sent him a fairly angry reply and heard nothing else - although one of the other recipients told me he hadn't harmed himself.

Over the intervening decade he has made repeated attempts to get in touch online, which I ignored until recently, when he started following me on Twitter. He told me he was recovering from a stroke, I expressed sympathy. He replied to a couple of my tweets, then once again attempted to add me on Facebook. I don't really use Facebook much any more so this time I accepted - it seemed churlish to keep ignoring him, and he's obviously unhappy and lonely. He commented on a picture of DD clearly (insanely) thinking it was me - saying I looked "About 12 - and lovely" which was a bit creepy. I pointed out his mistake and laughed it off (she's 10 - I'm 41).

Anyway, since then, he's messaged me out of the blue with increasing frequency, just telling me things about what he's been doing or comments about things I posted ages ago. Now almost every time I'm online I get those Messenger 'waves'.

I know this isn't a big deal, it's just irritating. I never reply to the waves or messages. We have no relationship. I feel that he thinks he is entitled to my time and energy and interest, out of guilt perhaps? Or just because he's a very important man (📯) and therefore I should give a shit.

What would you do? Do I just delete him? Do I draw his attention to my lack of interest? I wonder how many other random female acquaintances he does this to?

I might also warn your daughter that if she's contacted by a man saying he's an old friend of her mum's not to talk to him and to tell you immediately. I really don't like that he commented on a picture of her and don't believe that he's actually stupid enough to have assumed it was you.

Perendinate - that's so true - and so deeply ingrained that if I'd read my own OP as an outsider I would immediately have said 'block and delete'. But as the woman involved, my 'be nice be kind' response takes over.

Emotionally abusive ex used unsubtle hints and threats of suicidality against me when I broke up with her. Eventually my "Be Kind" indoctrination and sense of responsibility made me realise if I did sincerely want to help, I'd better get advice. Calling psych services for that advice led to me telling her that if she had genuine intent, I'd have to call Psych Emergency Team. Long story short, she tested me a couple of times then stopped. Never tried it on me again. Still alive.

Another recommendation for "the gift of fear" by Gavin de Becker here.
As others have said, ignore, block and delete.

Just ordered 'The Gift of Fear' - thanks for the recommendations. (And enjoying being online without being interrupted by random comments and 'waves'.)