UPDATE...
Ok so we went out on Friday night, and the bar crawl was great fun, and a great night overall. However, I'm going to be completely honest, I woke up the next day feelin like shit because of several holes in my game, and several wine/beer/guiness throbbin in my head!
Now I know you guys are going to tell me to man up, brush it off, and work on it, and I am telling myself the same, but it's not quite internalised just yet!!
Ok, so the girl. When we eventually met up (both of us were later than the official start time!) the first thing she said (after all the flirty tx game over the past week) was "Man, I'm so pumped for tonight. I've been looking forward to this all week EnglishAccent", so I was like

Everything started well - I made her beg for my attention and had her come 'collect me back' on two seperate occasions. I wouldn't let her have some of my guiness, while I let it go round the other ppl!! When she did eventually get it she got a bit of cream on her nose, and i lightly brushed it off with my finger, and then she took it with her finger and ate it!! Everything was going very nicely indeed.
When most people left and it was just me and her, and another group of girls chatting internally, I thought "Great, a chance to finally chat to her". Before I had barely got started my housemate showed up from nowhere, and joined us. Now she likes him, I'm certain of it, but he hadn't told her he had a gf of 3 yrs and that it wasn't going anywhere!! He also knew after the last time, that he needed to help me by NOT chatting to her in some corner!!
He kept his distance most of the night, and I had two more opportunities to flirt with her, which I think went particularly well. One involved messing around and trying on clogs, and the other one involved a wine (which I bought - possibly a mistake, she didnt ask or anything) and a 6ft pirate statue! She even rang me at one point when we got seperated, and interrupted when I was talking to another girl!! It was going perfectly!!
On a side note, she also said I was being "too negative" at once point, so I loosened my game, and let some of my smiley nice guy through, which seemed to compensate the situation.
Then, unfortunately, somehow, (and I can't remember how cos I was a bit drunk by this point) we got seperated again, and next thing I know she is sat with my housemate under an umbrella outside!! Maybe I should have interrupted, but I thought "no no, I'll let her come to me", but she didn't....all night!! Even at the next place, she went to an upstairs private part with just him!!
So I focussed my attention on two different girls, one POlish girl which I got seperated from (once again I think I need help on this!), and a NZ girl who I flirted with, and she had been reciprocating, but for some reason it all went really cold on the way back to hers.... so i ended up in her bed, and she ended up on the couch!!! At least I got the best nights sleep haha.
I have texted the Canadian/Polish since that night, really piling on the suggestiveness....too much I think. It was left on my text to her, and I haven't heard from her since.
Do I still persue her? (I think she is coming to our house party this Friday)
Do I have a word with my housemate (again!) about that night? (He is adamant he won't cheat on his gf, and Canadian/Polish now knows he has one!)
How do I stop getting seperated from girls? ie. Friends pulling me away
How do I stop girls going cold on me, when everythings going so well up to then? Is it possible for a girl to act flirty and touchy, with IOI's, and not even want a kiss?
Gah, I f*cked up. Would appreciate your thoughts and support on this one.