L.G.
T., I commend you for trying to save your marriage. That took a great deal of courage.
It sounds to me like your fears are real, and hopefully your husband is sensitive enough to recognize that he needs to spend more time reassuring you that things are ok. I agree with much of the advice already given - that you need to do your best to trust him, seek counseling, talk to him when you're feeling insecure, ask him to spend time with you on the phone or the webcam in the evenings.
That said, sometimes we can be our own worst enemies. My hubby travels a lot, too and is out of town sometimes 5 nights a week at a time. His parents had a tough situation when he was in high school, and so I know he understands how infidelities of any sort can strain a marriage. I trust him implicitly and yet, when he's traveling with people whose standards are a bit lower than his, I get these icky feelings, too. I feel insecure when I can't reach him and sad when he doesn't call. Usually I find out he's been working on last minute presentation changes the customer wants, getting a late dinner, or working out at the fitness facility. I think these feelings we get are normal, and probably more centered around our disappointment. We're thinking of him so often, so why isn't he thinking of us (ie, calling us?) Mens' minds are wired differently - I honestly believe he sometimes doesn't think about it or is being honest when he tells me he was afraid to wake me if I'd already gone to bed. That doesn't make it any easier to squash the "what ifs" in my mind. When they won't go away, I gently explain them and tell him I just need some reassurance.
I'd also try to gain more understanding of what a typical day is like for him. Is he working from sunup to sundown in a very physical job? Is he just so exhausted at the end of the day that he doesn't feel like doing anything but sleeping? If this is the case, maybe you could try romancing him - send him a note or card for each day he's gone or send him flowers. Surely he could make time to call you after something like that - and if he doesn't, then perhaps you have more grounds to worry. I might even be inclined to pay a surprise visit. This could do wonders for your peace of mind, and might even pay great dividends in your marriage, too. Be careful that you aren't going for the wrong reasons - ie, to catch him cheating vs to surprise him by coming to spend time with him. Or, if you are both spiritually minded, you might ask him to set up a time each night to pray with each other and for each other. Regardless of whether he prays with you, praying for him can also be effective.
My hubby and I sometimes chat online using Skype, a free webcam to webcam chat program with voice. It doesn't cost a thing for us to talk so we aren't worried about long distance charges or running up our cell phone bills if we talk outside of night/weekend minutes.
Hope you're able to find some peace about your situation soon. I'll be praying for you!
Best,
L.