Sometimes flakes take a long time to come around, I would just ignore them or keep it relatively friendly.
Even if a girl doesn't want to bang you, you can still try for her friends, roommates etc. It really depends on why she flaked-
1. She's flaky - Don't take it personally and pretend it never happened, but don't give her the opportunity to do it again
2. She had her eye on a different guy - He won't always be there, so be friendly
3. She's just not that into you - So here she either said yes because she's too nice, or she said yes because you were forceful. If it's the first, be nice back and hope she has friends who find you attractive, if it's the second then be nice and hope she relaxes her stance about you... so you can bang her friends
I've found that little good comes from showing that a flaky girl bothered you
Even if a girl doesn't want to bang you, you can still try for her friends, roommates etc. It really depends on why she flaked-
1. She's flaky - Don't take it personally and pretend it never happened, but don't give her the opportunity to do it again
2. She had her eye on a different guy - He won't always be there, so be friendly
3. She's just not that into you - So here she either said yes because she's too nice, or she said yes because you were forceful. If it's the first, be nice back and hope she has friends who find you attractive, if it's the second then be nice and hope she relaxes her stance about you... so you can bang her friends
I've found that little good comes from showing that a flaky girl bothered you