Duuuuuude... this level of the game is SO easy.
Were you to play this level of the game right, you could easily end up sleeping with her again. She probably won't end up the girlfriend, but I've been in this same scenario a few times where I was able to, at the very least, get a few more good lays out of the person. Therefore, what I'm about to give you is not advice about how to date her, but how to hook up with her again...
Basically, she's already set up the scenario: she asked you out for drinks. Subconsciously, she's setting up a scenario where, if you act right, she can get herself drunk and use it as an excuse to hook up with you. BUT, here's the kicker: you can't be overly-emotional or over-reactive to her. Meaning: you don't go in there talking about how much you miss her/want her/need her, and if she starts saying things like "yeah, so this other guy's been hitting on me lately, blah blah blah" you act like it doesn't bother you.
So what do you do?
1. Don't call her up to remind her that she mentioned going out for drinks with you. Right now SHE is pursuing YOU, so let her do so. If she doesn't ever hit you up again or forgets to, so what - BUT, assuming she's looking for a hook up or just really wants you, she'll most likely call.
2. Set up the date and time, then say "cool, see you there" or - if you're picking her up - "cool, I'll pick you up at x-time." Once you've done this, DO NOT CONTACT HER TO RE-CONFIRM. For one, it's not necessary - if she likes you she'll show up when she said she would, and if not, she'll flake. And if she flakes, GREAT - you'll know her true interest and don't have to deal with her anymore. And secondly, in keeping with the idea of her chasing you, she'll probably hit YOU up 30 min to an hour before to make sure YOU are going to show up. So much better when it's on the other foot
3. During drinks, NO SAPPY TALK ABOUT YOU AND HER.
4. During drinks, DO talk about any improvements in your life (real ones). This will show her that you didn't crumble and fall apart when she wasn't in your life. To a woman, this lets her know you're not dependent upon her for your happiness - which is actually a relief (guys that are end up being the ones that want to commit suicide if she leaves, and no girl wants that on her conscience). Also be sure to keep things lively and funny - no negative conversation.
5. Look for signals from her indicating where's she at with it in terms of wanting to hook up with you. If she's touching/kinoing you regularly, occasionally staring at you for a bit longer than expected, or throwing out sexual innuendos left and right, it's a STRONG possibility. If she doesn't, it's okay - it probably means she's on guard waiting for you to turn back into the AFC she got rid of a few months ago. Do NOT react negatively to her if she's not giving these signals.
6. At the end of the date, do NOT be the one to suggest going to either person's place. Remember, you're playing it cool now, as if your life is fine regardless of if you two are hooking up or not. Simply give her a hug, say "it was nice seeing you, we should do this again sometime" and walk back to your car. Now, IF she says "hey, why don't we hang out a bit at my place" or something else that hints at her wanting to do something more, it's your decision whether or not you want to take it.
Now, if you two don't hook up that night, that's fine - but the fact that YOU didn't even bring it up as a possibility will probably swirl around in her head for a bit. What's usually happened with me is, I'll do these "get reacquainted" dates, go home, and a few days later get another phone call from them saying they want to come over to my place to "hang out for a bit." Yada yada yada, they come over looking much sexier than they did on the "get reacquainted" date; they suggest watching a movie; we cuddle up on the couch; and the next thing I know... BOOM! TOUCHDOWN!
The point is, it may take a bit of patience, but I've seen and done this scenario enough to know that, if they're coming towards you, you can only mess it up by being too eager and aggressive; but, if you dial it back a bit and act like you're doing great without her (which you should be), you'll be surprised how effective it is at making them want to re-connect with you physically. Hope this helps!