Thanks for replying, I can empathise with that as it happened to me too often for my own liking.
If it were an ideal World, we would have a cell phone full of numbers, so we could simply let him have her and move on to the next one, like many PUA's advise you do.
But from a Personal view point when you fall in love with a girl, or at least develop feelings for her, more often than not you start to wonder if maybe you're doing something wrong and in trying to correct that, end up in a situation where you then start putting pressure on yourself.
But I once had a girl as a friend who I didn't fancy in the least, we were just 'mates' nothing more and one night over a bottle of Wine She started to tell me some secrets, that I have never forgotton.
(1) Girls just love to flirt with Guys, as they constantly seek reassurance that they've still got it.
(2) They love to be the centre of attention.
(3) They love to be daring and naughty.
(4) Forbidden Fruit is the Sweetest
(5) They get bored very easily and as such don't want to stand around, watching you fix up your Car, unless they can chat your Mates up, while you are doing that.
(6) Given the chance they would make out 24/7
(7) A Fat Wallet and or Flash Car can really help to make you better looking, as it helps to confer a lot higher status on them.
Whether or not you agree with that is entirely up to you but there's a ring of Truth in some of it.
So while you're paying all the Bills (for going out etc) and doing all the hard work of keeping her entertained, over time your efforts start to 'Flat Line' which is when the Predator, then seizes his chance to present himself to her as a guy who is new and exciting.
She won't see him that often as he dates other girls which only serves to make him more attractive but will turn up at her house unannounced to lend her a Video that they were talking about, on one of those nights when you don't see her and as he is a 'Mate' of yours then obviously you won't mind if they go out for a drink, after which who knows what might happen?
And then Girls start to wonder, why we are scared of commitment and won't Marry them.