Trucker's devoted girl

I have been dating a OTR driver for 5 years. We talk on the phone almost every night. I wait on him hand and foot when he is home and take care of everything.

I just found evidence that another woman has been on the road with him. He arranged ahead of time to pick her up and she was with him for a few days before he dropped her off. He has always sworn he would never cheat and accuses me of it all the time.

I have never cheated on him and assure him that I never will, he is all I want. If I mention to him that I know, will he stop? I don't know if this is the first time or not. Do all male truckers find a lady friend? Is it possible it was just companionship and no sex was involved?