I would almost be tempted to postpone or reschedule the coffee for a couple of days.... maybe tell her something came up and you need to meet a day or two later instead. That could show that you have been GAL'ing and aren't exactly available just waiting around for her.
I'm still kind of new at this, so hopefully others will chime in if that's a bad idea.
Just remember when you meet, be strong, steady, and happy. Try to just listen and validate, and try to not give any strong opinions one way or the other.
I offered advice to my stbx last night and it really backfired. She quickly got angry and left abruptly. :-/
Me: 43 W: 37 Together: 18 M: 15 D: 8 yrs old ILYBNILWY: March 2011 She Filed for D: August 2011 She moved out: Sept 1, 2011 Reconciled: May 2012 Divorce Case dropped: July 2012