I'm in my 50s with DH & teen kids. DB is a few years older, single, not married or in a partnership etc.
DH & I have both worked, are comfortably off and looking forward to paying mortgage off/travelling retirement etc. Have two teens who we hope to support through Uni.
My DB, after uni degree, has never really managed to settle into anything. Seems to fall out with people/ leave jobs. He is very creatively talented (photography), but won't put his work out there - is always going on about how people steal images online etc.
He hasn't really had a job since his twenties. I don't really know how he's managed - a combination of benefits, odd freelance work and being very frugal I guess.
(We live 500 miles apart, so I don't see him much, and he has never shown any interest in my family (doesn't send birthday cards to his neice & nephew) or what I'm doing - we've never really been very close).
A few years ago we both inherited some money from family and he wanted to buy a small house in a fairly remote town. At the time I questioned whether this was a good idea as he doesn't drive, so he is a bit stuck to the local area and bus routes, but he was adamant that it was what he wanted.
He didn't have quite enough money, so I loaned him over £10k of my part of the money so he could get his house. He asked for more at the time "to decorate", but I said no, that was all I could offer.
Anyway, now, about 5 years later, he says he wants to move, but can't afford all the costs etc, so can I lend him more money (over £1000).
I've said no, because I don't have spare cash (true) and I'm no longer working (true).
He keeps sending me emails saying how tight things are for him (he has form for this over the years...) and I feel like he is trying to guilt me into giving him cash. If I make any suggestions about him finding casual work, or joining online services like Upwork etc he just deflects it all saying 'there isn't any' or that the 'rates of pay are too low'. 
I've sent him lists of suggestions of websites to look at, and jobs I think he could do, but he has an excuse for not doing them all.
I suggested he sell a few bits and pieces on ebay (which is how I generate a bit of cash), but he says he 'hasn't got anything'.
I recently reminded him that I lent him about £500 when we in our late 20s and he never paid that back (I stupidly didn't get a receipt, and it was pre-email days). He now just denies all knowledge and says I am making it up!
Now I've found out that since 'I've refused to help him' he's started emailing his friends asking for money, but they have basically said the same as me.
I do worry about him, but I just don't want to lend him any more money. DH says he will just be back again in 18 months time with a reason for why he hasn't paid me back, and asking for more. WWYD?