How do you truly come to terms with the death of a friend?

Time. You grieve a lot immediately, then you learn to adjust. It's much more acute when it's family.

SPC (Join to see) I am sorry for the loss of your two friends. My father was an Air Force Captain who was killed when his plane crashed. I was seven. My mother died when I was 15. I had buddies killed in Vietnam. A very good friend was killed the day after I left country. Each person handles grief differently. I think of my father, my mother, my buddies, and others, at various times throughout the year. Are some of the memories still painful? Yes. I try to focus on good memories and hold these memories close.

A person never comes to terms with the death of a friend or a loved one. You just learn to live with the loss

Update to all;

I appreciate all of your feedback. One of the things, pretty much unanimously said is "don't bury it or bottle it up." I agree with that sentiment, and always have. However, new issue arises: I am not being given any opportunity to grieve. I've literally been told by both of my leaders to --and I quote-- "Get over it. Death is a part of our way of life, and I've had it worse than you. So suck it up and stop walking around here with a chip on your shoulder."

One of those friends was a co-worker. How in the hell am I supposed to just make like everything is alright?

I've seen this from both angles - as the one suffering loss and as the minister trying to help people cope. There is no easy answer. The best advice I can give you is to share your grief. Don't wallow in it but do acknowledge it and speak to those close to you about it. Certain strength and comfort comes from the close association of others around you, especially if they share in the loss.
Now, saying that, there is a simple fact of life that we all have to deal with at some point in our lives. We die. Our loved ones die. Our friends die. When we lose someone we care about - it hurts - a lot. And in some ways, that pain will never completely disappear. It will fade. It will ease somewhat. But every so often something will spur a memory and we will need to deal with it again.
A personal faith helps many but if you don't have that - you have friends and family. The last thing you want to do is bury your pain. It will resurface later when it is most inconvenient and probably beyond your control.
See your chaplain -- even if you are not a church-goer. He might only be able to listen, or maybe there is more he can do. But he can help either way.

There is no easy answer to this, my friend.
I had a period of grief not too long ago that absolutely crushed me.
The solution for me was to get out from under that news and live life. The sun still came up in the morning, the kids still needed their daddy, and the fish were biting on the weekend.
It took a long time to come to grips with it, but I did.

Sorry for your loss. See your chaplain's office/Family Services for grief counseling either one on one or group counseling.....................

You never get over it completely. I lost a friend in Vietnam. He had been in country less than 2 weeks. I relive that morning a lot...

SPC (Join to see) First, and I am very sorry for your loss.
I would offer that you can't try to figure out why. You most just focus on the positive memories of your friends. There is no answer to who, when, and why, especially when we are speaking of young men and women, at home and even in combat.
It is never ever easy, especially to family and friends. I could tell lots of stories about my 33 years in the Army, but I will stick with the personal.
In last two years my father has passed away, along with father in law (I met my wife in HS). Then this past year the 20 year old daughter of close friend ours committed suicide, and in the same year, so do a close friend of my son's... For the family friend, my wife did not want to attend the funeral, as she just did not what do say her friend. But, the important thing was just being there for mom and dad, so we went. They appreciate that.
For the friend of my son's, he was the last person she ever saw. When I asked my son how he was doing, he said he felt like he had hole in heart. Sound familiar? I could do nothing to help, but listen. He was not even going to attend her funeral, as he did not know how to act... but, I encouraged him to go for her family, and they and he was happy that he did. They sent him a hand written note thanking him for his friendship and for being there. I suspect, he will cherish that note.
There are No easy answers here my friend.
Take a deep breath, cry as much as you need to. Try to always remember the good times, not the bad.
If it is too much to handle, go see your chaplain sooner rather than later.
Again, I am very very sorry for your loss.

Sorry you're having to go through this SPC Pietrantonio. I wish I had some magic piece of advice that would cure the hurt, but I don't. I lost over 100 friends in VN, some who I gave your typical black humor remarks as they left on their last flights. My daughter died a few years ago, her son was killed in an accident last month and another Marine friend died yesterday. You'll hurt forever, it just becomes a different hurt. But you asked the correct question. "How do you come to terms with [it]...?". I always throw myself into my work to take my mind off of my grief. A couple other respondents recommended seeing the Chaplain. It's not a bad idea. Even if you aren't religious, one of the beauties of the Chaplain is he/she is out of your normal routine and they should take the time to talk out some of the questions and feelings in your mind and heart.
You will survive, but there will always be a part of you that will hurt and it won't be any easier the next time it happens.