As for why I didn't invite her over.Why didn't you take her back to your place for sex? Talking after dinner -- good option for nightcap at your place.
You are going to get laid this weekend if you directly pay for sex. Your indirect payment for sex with a dinner didn't work out for you.
1. I didn't want to look desperate.
2. Since I've mainly relied on escorts to get laid for 8 and a half years now, I've pretty much lost the ability to sense when a woman is dtf (and my sensing skills were never tremendously sharp to begin with).
Regarding the nightcap, I don't have any alcohol at home anyway. For me, consuming alcohol is more of a social thing I do when I'm out (we both had one drink during dinner).
You're right, I'm going to get laid if I directly pay for sex this weekend. The dinner date last weekend ended up costing me about 40 dollars. Even if the dinner date this weekend were still on (and it ended up costing me 40 dollars again), 80 dollars is still cheaper than escorts. That's why I was willing to go the sex-via-dinner route.
With escorts, however, even though they're more expensive, you get a sure thing. Sex-via-dinner is never guaranteed.