Should I trust him?

I discovered my husband had some intimate texts with another woman by accident. Then I checked his phone bill list and found a lot of messages and phone calss made in midnight with this woman. My husband told me that there was nothing going on between them except for some chat when he felt lonely. We have been working in different places for several years. I understood he may feel lonely sometime and I don't mind he has good female friends but he should let me know that he has such a friend.

Then I recalled that 2 years ago when I was back on vacation. She called him in midnight (we already off to bed). He answered that he was not in charge of that work anymore and asked she to contact another person. At that time, I did not even think that how she could call him at midnight for work? I was so trust my husband and I did not even suspected that something was abnormal.

I have been working abroad for several years. If talking about lonely, my situation should be tougher than his. Many men came to me but I turned them off.

My husband was my first boyfriend and then became my husband. That means I was never with another man in my life. I felt very disappointed with him. It has been one year, but it still bothers me whenever I get in touch with anything (news, situations etc) similar. I thought about divorce many times but I don't feel brave enough to do this.

I am 35 years old now. I don't know how to start if I get divorced because I never imagined divorce in my life. I lost interest in him but I felt so hard to make a dicision to divorce. We both get along well with both families. It will be like divorce a whole family.

If I continue this marriage, sometimes I turn upset suddenly.

He treated me good when I was on vacation. I really don't know what's the right thing to do. Anyone can give some advice?