Hello,
Please help me come out of this.

I got engaged 6 months back. It's a love alliance. Approx 5 months before our engagement, I came across few mobile bills of my would be fiancé. Which told that he has been messaging at midnight with one of his female colleagues who is a divorcée.
When I confronted him about this he said the lady was making physical advances toward him. And he was just trying to shoo her away. I cudn't buy this story but still I had to agree with him. He also promised me that he won't ever message her again after this. Week, I again got hold of one of his mobile bills that showed that he has send few messages to her in 2 months prior to our engagement. When I asked him about this he said she messaged him and he had just replied. There was nothing wrong in his mind. He had cried a lot for past 4 days. In normal situations I would have handled this But he is a brain tumor patient. When ever he get upset, tense or cry his condition gets worse. He lives alone because of his job. When his health deteriorates, I get so scared that I forget whatever he has done and reconcile with the fact that I have to accept everything for sake of his health. I knew about his health before our alliance and its my own decision to have this relation. BECAUSE I LOVE HIM A LOT. But I don't understand what should I do when I get to know he is cheating upon me. If I talk about this he can't handle but if I don't I get frustrated. Please help me what sud I do I am losing my trust on him. I am afraid I'll neither love him or respect him for what all he is doing to me. Do I deserve this for loving him? Or should I accept everything because I love him