How do I tactfully put off an admirer?

[Milmoo]

Hi there, this is my first post on here. I am recently separated (within last 4 weeks) and am away in New Zealand staying with family for 6 weeks. I have been friendly with a fella at work, nothing more than friendly chat. We are friends on Facebook and to while away a bit of time I have been Private Messaging with him. He knows that I'm separated and, by the sound of things, he's not getting much from his wife (ie sex). Anyway, one thing has led to another and our msgs have gotten a bit sexual. Maybe I was giving him the wrong signals, but I thought it was just a bit of harmless banter albeit of a sexual nature. Only he obviously thinks there's more to it and wants us to get together when I get back to the UK. I am in no way attracted to him, but I do want to keep him as a friend. Any suggestions as to how I get the message across to him that 'it aint gonna happen'? I still want to keep up contact on FB with him so I don't want to unfriend him. Help please.

Find hunky kiwi man. Post photo of him and you with arms around each other on FB. Done. I'm in NZ, you can borrow my hot husband for the photo if you like

You can't keep someone like this as a friend. He'll interpret any sort of amiability as a green light to keep trying his luck and that's only going to get messy

Don't believe the stuff about his wife - that is most likely rubbish. Just defriend him (or whatever the facebook term is) and ignore him completely. The only way to deal with this kind of thing.

Oh the old my wife doesn't understand me chestnut!

First of all I think you need to get out of your mind that you can be friends with this guy. The minute the sexual messaging happened that possibility was ruined because he is married and clearly after an affair.

You'll get yourself in a world of trouble if you don't explain quite clearly what you have here - that the messages were a fantasy which you do not want to make into a reality and that you think it is best to cut all contact now.

Honesty generally works. Try this: "This is getting a bit heavy. You're married and I'm not interested. Take care."

No gentle hints or posting of photos with a hunky Kiwi.

Be honest. 'Its been fun, but it has gotten out of hand. I don't want to hurt your feelings or harm your marriage. I am not interested in taking this any further and won't reply to private messages any more'.

Don't flirt with married men on FB. It will all end in tears.

Block and delete. If he asks you don't have facebook anymore.

Thanks everyone for your replies.
I agree that I should be up front so I've messaged him and told him that things were getting out of hand and that we should backtrack to just keeping it friends only Explained that I was uncomfortable with the sexual nature of the chats taking into account he is married etc. He was totally cool about it all, and so we remain friends. I am confident that I can now handle the situation with him, and he knows that nothing will happen further when I return to the UK.
Thanks again everyone.

Oh, forgot to add .....
Kiwiinkits great idea about finding myself a cute Kiwi guy. That would be awesome :)