(((Faith)))) The "not knowing" is the worst for sure. It is the memory of what once "was" that is keeping that small part of you clinging to hope. You may never "know", and for us humans that is oh so hard. We want to "know' as if that will change or make things better. If he is alive, then you will constantly wonder where, what, and how he is doing. If he is not alive, well, then at least (after the guilt goes away) you will have closure. What is making you upset and sick with worry is the fact that another person is "controlling" your emotions. That is why (and SO hard to do!) it is important to learn to detach from your emotions. I don't know if you meditate (which is different than praying), but if you do, while you are "sitting" let the emotions rise and fall like waves. Examine each one without getting attached to it and let it go. Emotions are really just complex chemical reactions in our brains. Detach and things will become a little easier.
Of course, all this is great in theory, hard in practice! I know!!
I hope this helps.
Hugs & prayers for you, my dear.