The most important thing is to sort out your relationship with your current spouse. You will need to decide whether you want to continue with this existing relationship. You are responsible to your spouse so you must sort out this relationship before devoting to a new one. Evaluate your priorities and you should be able to figure out what is most important to you.
You're married, I hope you're not contemplating having an affair. It's a shame you have these feelings for another & not your wife. Before breaking up two families you have to put some work into your marriage. Give it a chance, try to see the good in your relationship, remember the things that drew you to your wife & try to rekindle those feelings. It is not fair to your wife that you're cheating her out of your love without her knowing. If this continues I would suggest letting her know. The other women can't be a great catch either, emotionally cheating on her husband. If she decides to leave her husband for you, careful it could come back to bite you. Loving someone & living with someone is two different things, take your chances. I hope you make the right decision & give your wife the chance to make a choice for herself as well.
Stay Away!!! Try to strengthen your relationship with your husband. Cheating on your husband, no matter how right it feels, is the wrong way to go. Might I ask, how is it that you are in love with this person? You've already crossed the line. You should love your husband!
How did you let something like this happen? Have you no respect for your wife (or husband) & your marriage? How about your children? Or the other person's children? Granted, just because we get married doesn't mean we stop noticing attractive people, but we are suppose to be mature enough to control ourselves. It's time to come clean with your wife (or husband) about what's going on, do whatever you need to do to distance yourself from the other person, & get counseling & work on your marriage. I've known more than one couple that has had something similar happen, & has either moved (as far away as Alaska) or undergone a sudden change in jobs to avoid temptation. You made vows, to forsake all others & stay together for better & for worse. It's time to live up to that.
It's going to be hard for you to establish a long term relationship together. You're thinking of taking on a woman with a proven record for cheating, she needs to gamble on you staying faithful to her when you've already cheated on your wife.
If you two were runners in a three horse race you'd both be rank outsiders.
I'm sorry if that sounds judgmental or critical but you did ask and those are the facts.