Serious question about yeast infection.?

I have a yeast infection. I have only had one other yeast infection and it was from a man i was dating and was cheating on me. I am married and now I have a yeast infection. I cannot think of any reason I would have a yeast infection unless I got it from him. Besides antibiotics, (which I have not taken in a year), and prednisone (which I have not taken in 6 months) is there any other cause of a yeast infection?