You're normal! You're just tired and stressed and overwhelmed not only with your daily chores but with the thought of him being away. It's wonderful that he lets you know how attractive and interesting you are, and that he calls you regularly to let you know he's thinking of you.
Your first mistake is in thinking he's not interested in the details of your day. Just because you do them every day doesn't mean that they are boring or less valuable. Maybe he wishes he could be part of it and would like MORE details! Tell him the silly things the kids did, or what they said. Take some photos with a camera or a cell phone, and email them to him - maybe he'd like to see the leaf collection or the stack of blocks or the craft project!
Your second mistake is in thinking the outside activities you engage in are somehow not valuable or interesting. Do you have any idea how many people wish they could do fundraisers for diabetes or cancer, or who wish they had a talent that was needed for volunteering at school?
I suspect that some of that old ppd may be lurking in the background. Even if it's not depression, you have hormones raging and I'm quite sure you aren't getting enough sleep. You say you aren't the "insecure type" but still, all these insecurities are bubbling up. So admit that they are there and try to confront them.
Can you peel off some time somehow to do something ADULT? Can you switch off with another mom for some child care, and go to an art museum or the science museum? Can you take your kids to a children's museum? A lot of times the library has free passes, and you'd be amazed what adults can learn in a museum geared to kids! There are always things you can learn at your level while they are learning at their level.
Date night! Pick out a movie that requires some discussion. If you can't go out, find something on TV or Netflix that you and hubby can put on after the kids go to bed. While he is away, maybe you can find something that you both can watch in your separate locations and then discuss. Read a book - I know I know, who has time? But let the laundry go, don't make the beds, have cereal for supper one night - and find some WOMAN time (not just MOM time). Join an online book group.
Get an in depth news magazine like Newsweek or Time, and read up on a pressing issue - you'd be surprised at what's out there facing all of us that needs good analysis. You have a brain but you just feel like you haven't been using it. And I'll be you have a lot more to say but don't trust that it will be of interest to others. But that's not true. Like anything else, conversation takes practice.
Take advantage of the time he is away to relax some of your at-home standards just for a little "vacation" and take care of yourself! I know you will miss him, but in some ways you will have more time to focus on yourself, so you can put the time to good use!