Who can explain this attraction to me* i am a woman*?

She and I are both in our 30s and always been hetero sexual. but ever since we met we have been attracted to each other. It started as flirting...then a year later we started kissing...then a week after that touching...then last weekend we went all the way . And we have to spend as much time as we can together and love touching and everything ! BUT we can't tell anyone since technically were not LESBIANS or BI since we have never been attracted to or interested in other women! WHAT is happening ?