Also, women flirt for a lot of reasons that have nothing to do with actual interest. They'll flirt at a restaurant to get better treatment. They'll flirt because they're bored. They'll flirt because they want to see how you'll react and talk about it later w/ their friends. I'm convinced that women flirting isn't a good indicator at all for interest, I need actual, verbal confirmation.

My wife had to be pretty direct with me before I got the hint. When we met, she signaled to me to come over (she was w/ a group of friends), asked for my number, and texted me first. I have been conditioned that approaching a woman in a group is generally a bad thing, asking for their number is creepy unless we've already hit it off, and texting first can also be creepy unless it's for a specific reason (e.g. I had a good time, want to do X?). But women get to do all of those things. I'm happy to initiate (and I did for our first real date), I just don't want to be labeled a creep.

So I just treat any kind of flirtation as an indication that they want something from me, and avoid acting until I know what that something is. So please, be direct. It's not that I don't notice the flirting, it's that I'm unsure what you're looking to get out of it. Verbal confirmation confirms it, and at that point (you don't need to say "I like you," but something like, "I'd like to get to know you"), I'll be much more interested in reciprocating (speaking as a generic man here, not my married self).