I agree with Vic in that she said this for her own closure and to not leave anything unsaid. However, the sentence of “When I got married I thought you and I had no future together” sticks out to me as a way possibly wanting to leave a door open. I interpret this as her meaning that she married someone else because she did not think the two of you would be married. I say this because I told the love of my life something similar with the intention that he would know the door was still open. It is not that I wanted anything to be rekindled with us right there & then…but I wanted to let him know that I still had feelings for him. It took me 15 years to be able to tell my ex this because I had not processed our break-up. I had to accept and workout my feelings for him as well as acknowledging my part in the relationship not working out.

If you find that you are over analyzing the reason for why she told you this now, I would take Vic’s suggestion of asking her. Then you can let go for good.