Girls send text messages on business trips, but no one answers.

Love is based on trust. Since you love her, you trust her 100%. If you think she's having an affair and you can't accept it, that's the beginning of love collapse. It has been shaken, why care about cheating? In addition, when you have such doubts, it usually happens. Your girlfriend will give you the feeling of cheating, so she is not a good girl. Let go.