My rule is this: Accept every other invitation. Sometimes you've available. Sometimes you're busy. That is the best way in my opinion to establish a connection and create mystery/GAL at the same time. At least in the beginning this is a good way, but as time goes on you can accept more invitations.
Never invite yourself, or invite H. At least not right now.
I would have responded with this, "Sounds like fun, but I'm busy tonight. Maybe some other time."
----"Et tu, Brute?"---- me:28 W:24 S4 T:6 M:4 EA Exposed: 5/21/10 Bomb: 6/20/10 (Father's Day) NC w/ OM: 7/10/10 W moved out 8/21/10 http://bit.ly/aOrZne - My sitch