I also have fear of the night time. As soon as it gets dark it's like I feel my safety net is gone (the light..things being open and me being able to get help if needed). It's used to be so bad that I would stay up all night because I was scared that if I fell asleep I would not wake up. It's hard to overcome this fear. But with CBT and medication it got easier and now I only occasionally get so scared that I can't sleep.
Walking and keeping busy during the day does wonders. I think walking outside is great for anxiety. Having a hot bath or shower beforehand may help too.

This is obviously an old post, but yes, I know what that is like. My attacks almost always happen at night (the most common exception being on planes). It can become very debilitating. And, like you, I have a family to support and a mortgage to pay, so I can't just let it take over my life.

Try to stay strong. Seeing as how the original post was over 3 years ago, I hope the OP has gotten better.