I think the coolness after the date is natural. She saw a different side of you on the date and opened up a bit. Now she's afraid the changes are just temporary and so she's pulling back to protect herself. You must just keep the detachment and being pleasant and fun to be around. Be Calm, Consistent and Constant. Over time she will get more comfortable with the new you. Just keep working on yourself. Keep looking at what drove a wedge between you and fix your part of it permanently. It may be hard to do but well worth it. If she doesn't come back, then there will be a better you for another lady to fall in love with.
M: 59 W: 53 M: 9 yrs T: 14 yrs No kids together but D30(hers), S27, S24, D21(all 3 mine) W moved out 11/18/2013 D-Day 12/14/2013 W moved back home 12/1/2014