after how much time, reconciliation is not possible..

i had a breakup 6 months ago..is this very long time?

You want to get back together? I guess it depends on why you broke up, im not a great believer in things never working out when you date an ex for the second time. I dated my bf for 3 months, then we broke up, spent a year apart with only the odd text/contact, then we got back together and have been together a year now.

Only if you didn't break up because of cheating, or later on found out that your x was a cheater/ liar, and still have fond bonding to her, and vice versa from her side.