As a Muslim brother, it is imperative that you bear in mind the fact that you have violated the rules of Shari`ah by developing such a relationship with a married woman and so you have committed a grave sin. Therefore, you have to cut all relations with this woman and sincerely repent to Allah.
Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states: To get close to a married woman is loathsome, disgraceful in Islam, and is a most heinous sin that brings the wrath of Allah. The woman involved in this relationship is guilty of an even greater offence because she has not only betrayed the trust of Allah but also the trust of her husband.

As a Muslim, you must immediately put an end to this most heinous sin and never return to it. If you marry her, it is like two adulterers marrying each other. You must, therefore, sincerely repent to Allah by earnestly seeking His forgiveness. Repentance is not complete unless you feel a deep feeling of regret and sorrow for the violation and disobedience you have committed. Refrain from all such associations and relations immediately, and make a firm resolution never to do it again.
If a woman, or man for that matter, has marital problems, she/he must find solutions through positive channels that are healthy and lasting; the remedy does not lie in forming illicit relations with another man/woman while still in the bond of marriage. One wrong does not justify another.
as far as you are concerned, it is important for you to safeguard yourself against such temptations through marriage. No respectable Muslim or decent person would ever chase after a married woman to take her out of the marriage bond only to marry her instead.