Q: I talk to my gf and a whitish presemen fluid comes out. We are engaged. we going to make nikah in august. Does my fast break.

A: Limit communication between yourselves. You have an entire life to communicate with her. Practice a little more patience and Allah (SWT) would inshaAllah bless you both.

Your fast did not break by the mere release of precoital fluid.

Allah Certainly Knows Best.