That's a question only you can answer.
You must have been interested to allow her to keep her hand there for so long.
Are you curious about what it would be like with a same sex partner? Be sure you think this through. Your husband could cause all kinds of problems because of the challenge to his masculinity. If you have children you could lose them.
However, if you truly seek a relationship with this young woman, don't deny yourself a life's worth of happiness.
This will take a lot of thought. Best of luck.