I decided to stay with my husband after he had an affair. What is the best way to cope with it?

I decided to stay with my husband after he had an affair with our babysitter. We have two young children and I love our family dearly. I chose to forgive and give him another chance to prove his love to me. However, it's been very difficult for me to move on due to the pain he has caused me. It's not easy to forget about what he has done and I often wonder why he would risk a lifelong commitment with his wife and children for a moment of bliss. They didn't go through the whole nine yards of ual relations; however, he gave her . It's extremely painful to know that he has pleasured another woman and has given a part of himself in which he is only to share with me. How do I get through this whole ordeal and not let my pain overtake me? How do I become stronger from this situation? Please help! Thank you so much!