What's "we can catch up sometime" meaning ?

Hello

I met a girl and we hang out a lot, but before that's become serious she avoided me (because I will leave for one year). That's hurt me a lot and I said some ridiculous declaration.

After 3 months and lot of try to see her, I sent to her some gift from my last travel (I didn't have time to give to her) and a letter to have another chance. And she answered thanks blahblah ..." We can catch up sometime... I feel bad that I might have hurt you a lot in the process... I am sorry..." what's "We can catch up sometime" meaning ?

It's a long time I don't see her but I know she have a bf...
Updates
+1 y
why then I have no answer for a drink I don't understand ... :(
What's "we can catch up sometime" meaning ?
Post Opinion