bchboy1206, she is not interested in you. She is interested in using you.
It seems her husband can't or won't provide all the attention and validation she feels she deserves, which is prompting her to look outside of the marriage to satisfy her needs. That says a lot about her character. Just by approaching you she is making this a bad situation, because she will feel unwanted if you do not give in and she will feel like a slut if you do give in, thereby dropping her self-esteem even lower in either case.
At least you can avoid the major trouble if you ignore her requests and do not put yourself in any kind of situation that she can hold against you later on. You'll be walking down a dark, dark path that leads to nowhere if you allow temptation to get the better of you. Even if you were to ignore the fact that it is morally wrong -- put yourself in his shoes and imagine how you'd like it -- the outcome will not be happy. If she does leave her husband eventually and settle down with you, there is a good chance that she would cheat on you just as easily. Worse, if she does not leave her husband, she will have power over both of you, and you would get the worst deal of all. If she wants to hurt him and/or make him jealous to gain more attention, she might mention that she is sleeping with someone else. He'd come after you. If she wants to continue the affair but you want to get out, she might threaten you with mentioning the affair to him. Again, if he'd find out, he'd come after you.
Stay as far away from her as possible. She is a rotten apple.