Has This Happened To Anyone Before?

So I am on CD 50, and 30 DPO. I'm still getting negative pregnancy tests. My cycle lengths can be somewhat irregular, but the longest it's ever been is 47 days. I'm at my wits end! I don't know what to think anymore. I tested this morning and it was still a BFN. My husband and I have been TTC for over a year, and I get so frustrated when I get my hopes up and it's still negative. Has anyone had this happen? Does anyone have any advice for us?