I used to get migraines even before I started in school, but they were very infrequent. Then, through my teens, they only hit when I was under severe stress. I didn't know what they were, but they would completely immobilize me until they went away. Immitrex didn't work so well for me, but no one told me to take them early in the attack. (We have sucky doctors in Delaware...it's the malpractice mecha of the USA)
As mentioned before, it seems that sinus problems and insomnia go with many migraines. Your experiences seem to be suggesting that this is true, which is interesting to know. My grandmother also has all 3 of these problems.
Anyway, more things that help me with migraines:
Going outside and taking a walk, though this was too difficult when they first got severe. Sometimes, sitting in the bathroom with the fan on helps. Maybe something in the air here is bad for me. We also tried getting "air cleaning" plants.
Exercise (though I understand this makes them worse for some people...it used to make them worse for me, but no longer does).
Getting enough sleep and REGULAR sleep patterns. If I stay up late on a Friday because I'm off that weekend, I will likely have a migraine the whole weekend. Which sucks, BTW.
Migrelief, which I mentioned earlier, cut my migraine recurrences in half. But only after I took them for a couple of months. You may not realize it's working until you stop taking it and suddenly you have them all the time again. It works gradually. You can get them through Amazon.com with free shipping if you can't find them locally. They even mail them out every 30, 60, or 90 days if you want them with the free shipping and a discount.
I avoid artificial sweeteners. I probably have allergies.
Loud music. (Again, this would not have worked for me in the early days.)
Eat some food. Eating regular meals is a good idea, too.
With the last two, the effect can wear off quickly once you stop. But it can give you a break at least.
Visual imagery/meditation can be of some help, though it's hard to do this when the migraine is in full blast. Like so many other things, you have to start working on it as soon as you think you're getting one. You can try imagining that the migraine is a flame, then imagine the flame getting lower and lower. Then try breathing slowly through your stomach, which should lower your heart rate. You can breath starting with the stomach, then fill the lungs, and out with the air if you like. This sort of thing works with other issues, like stress and other forms of pain, too.
Try imagining that your JW in-laws are a fire that gets lower and lower...Oh. Sorry. Snuck that in.