I just want you to know that you're not alone. You're far from alone. There are thousands of other people who are in the same exact position as you, and there are much more who have already gone through it. There's also me who is currently sitting at home while my boyfriend is deployed.
Trust me, I know it's not easy, and it seems like the days are never ending while they're gone. I promise it will be over someday, and that's something to look forward to. I can't tell you how many nights I have lost sleep because I've been worried about him or just because I missed him so much. I know- I've been there. Here's my advice, take advantage of the phone or video calls even when they may be at extremely inconvenient times. They're worth it, and keep a smile on your face for days afterward. Even if the call is for a few minutes, take it. You don't know when you can get another one, so take advantage of it.
Holidays are hard. With Thanksgiving, Christmas, and the New Year just passing, it seems harder than normal to get through it all especially with the whole family having their significant others, and them asking about yours. It's hard, and it seems like it will never end, but take a deep breath. I know you want them there, but it will be over soon enough. Take it day by day, and I promise you'll be able to make it through other holidays and maybe even birthdays.
Give yourself something to look forward to. Even if they're little milestones. I've found myself counting how many months my boyfriend has been gone, and it makes me extremely happy when exactly a month, two months, etc., passes because that means the deployment is that much closer to being over, and he comes home sooner. Of course, counting down to when they come home is awesome, too, but it can be sometimes difficult since you don't know when exactly that is. So, make goals that you know are for certain, and it helps quite a bit.
Again, I know it's hard, but it isn't the end of the world. It will be over someday. Take it day by day and look forward to what is over and what there is to look forward to. Find someone who is also going through it (or has gone through it), and talk to them. It's comforting having someone knowing exactly how you're feeling when sometimes there aren't words for it. I promise you will both get through it, and be stronger than you were before the deployment (cliche, I know). Keep your head up, and power through. You got this.
Someone in your shoes