Love or Lust? It doesn't make much difference. He was wrong. If you condemn him you are wrong. If you condemn his actions, that's ok. I only know of one man that never made a mistake and I celebrate his birthday around Christmas time.
However, if he wants to make ammends and wants to repent of his wrongs, I think you should take him back and work on your marriage. Marriage isn't easy. Its the toughest job I've ever had, but it is also the most rewarding.
If I were in your shoes, I'd get the movie, "Fireproof" and watch it with your husband. I'd get the companion manual, "The Love Dare" and follow its instructions. Read the books, "The Proper Care and Feeding of Husbands" and the "Proper Care and Feeding of Marriage" and follow their instructions. You will learn a lot of things about your husband, what makes men tick. He will learn a lot about you and what makes women tick. Make it a point to discuss the movie and "The Proper Care and Feeding of Husbands", the items you find inside and have questions about of the "Is this really the way you feel?" with your husband. A whole new world may open up for you and him.
Plan a cruise on the Princess Cruise lines. Princess was the setting for the TV series, "Love Boat" and they go out of their way to be nice to couples celebrating anniversaries. When my wife and I sailed with them they invited all the couples celebrating an anniversary to come to the auditorium. We almost filled the auditorium. The longest marriage was 62 years and several couples were on their honeymoon. Many couples were celebrating 1st and 25th anniversaries. We had a wonderful time. (If you are used to buying lunch while at work, if you brown bag it and save the money, buy the end of the year you'll have enough money to pay for a 7-day cruise for two.)
If you and he will work on your marriage and learn from these books you can rekindle the love and fire in your marriage and end up with a much stronger marriage. Your kids will be better off having loving caring parents that are their parents. Be sure you treat him like a gentleman and he treats you like a lady. If you want to know what that entails, ask. Your children will learn a lot by your example. (At least it works for us.)
Good luck to you and yours.