Phil

you were looking at her as a play thing, a shag, a bit of a laugh - so naturally, when you ahve no feelings for somone and are not looking to get into a relationship sex with that person is boring, especially when you have plenty of girls to fuck-- you end up wanting somthing a bit different a bit naughtier.

from her point of view no matter what she said to you regarding her wants - she really wants a relationship with you and doesnt want to give you everything you desire straight away as she feels that if you are just in it for a good time you will then get bored and do one.

another problem is hot girls are not used to guys that value themselves highly and often dont know how to act, they carry on with the 'every guy loves me' mindset which is completely incompatible with you.

Phil might i suggest you venture into the world of foreign chicks - they are ace in bed, eager to please their man, hot, often are slim with big tits