This is happening to my partner (ps4) and myself (pc) as well. It has become worse over the last couple of days to the point where I can't log in without disconnecting. It has been happening since June 4. We play from Sydney, Australia and there are a couple of threads going around about this same issue.

http://forum.square-enix.com/ffxiv/t...NA-Data-Centre

I have logged a support ticket with SE but am yet to hear back. Where are you playing from?