So I'm 22 and I went out with a woman last night who is 40. We met online with the intention of starting a strictly sexual relationship. Our "date" last night was kind of a meet and greet to see if we were compatible. Well, everything went perfectly. We saw a movie and then we talked for about 2 1/2 hours. During that time we made out and groped each other a little. Basically, things were going so well that I could have had sex with this woman, but she had to pick up her kids early the next morning so we both agreed it would be best to do it another time.
With that said, here is the problem. I'm not attracted to her at all. On a personal level I like her a lot, but on a physical level there is barely any spark on my side. I told her I'm attracted to her, I told her I want to have sex with her, but I really don't and only said it not to hurt her feelings. What makes things worse, I don't get the feeling she has a super high self-esteem in regards to her looks so I don't want to be honest and say the physical chemistry isn't there. She isn't ugly, but maybe a 4/10. I dunno.
So what do I do? How do I get out of this? I don't want to just ignore her, cause that seems kind of rude. I'm thinking of telling her a lie, like I got family issues or something. Anybody have any good ideas? Maybe stuff that has worked for them? Any help would be appreciated.