Hello Jeffer,
It is hard, to give specific support without knowing many more things about what is going on....But here are a couple things for you to think about that may help you understand, while your son is not communicating very well. First, you used the words " very depressed" .... now adays many people use the word " depressed " where we used to use the words sad and angry. Unless he actually communicates with a mental health professional....depression cannot be diagnosed. So hopefully, at some point he will choose to do that, in case he needs medication and or therapy. Second, a certain amount of withdrawal and anger is normal when adjusting to a health condition with an unsettling prognosis. We actually go through a grieving process, where we grieve for our healthy self and the life we imagined we would have....... which now we have lost. You may want to read up on the stages of grief and what can be done to help some one through them. Love him instead of worrying about him.....He may not choose you as his confidant because your his mother and he doesn't want to burden you. Is there a close friend or other relative that might reach out to him? Anger and lashing out are more common coping mechanisms in men. Anger and lashing out makes them feel powerful and in control in a situation where they are somewhat powerless and vulnerable. If he was never one to verbaliz his feelings in the past, he won't have the skills to do so now.

So, tell him you love him, tell him you recognize how hard it is for such a strong vibrant person to find out he is so ill .....and tell him that when he is ready, you will help him find a professional to teach him how to cope with his illness without lashing out at those who care about him.