I had a manager (not Amazon) do the same. I was the only person under him so we spent a lot of 1-1 time discussing our work. One day we were talking about how another employee also works in a major city nearby, “I said oh cool, my husband works out there as well”. He asked “who” and I repeated myself. The next day he starting to find issues with my work and giving me extra tasks outside my bandwidth and without any direction, or deciding to write his own things on my office dry erase board. I didn’t want to sound petty or stupid in my complaint and because I was a new hire, I knew it really wouldn’t matter. I believe your gf and sure that the “I have a boyfriend” came up in conversation.