It's all a balance between enough beer that she starts looking good, and too much beer that you don't get it up
Seriously though, if you don't think she's hot to you, then she probably never will be. It could be that she has issues, and she's hanging out with you because she knows you don't think she's hot, and she likes that you just hang out with her without it being all about sex. I've had a few female friends who were OK-looking, but there just wasn't a spark.
Charles