over my head?

1 post / 0 new
over my head?

hello all.  first time poster here. 
im not sure if I out this in the wrong sub forum, my apologies if so...

​Long story short, I have been a caregiver for almost 5 years for a very dear friend of mine who lives with me. He's been thru the ringer; from SEVERE combat PTSD, numerous cancers and being treated like trash at the VA which cost him most of a collarbone, part of his neck and his dignity. Whole nother story on that mess and it makes me so angry for him....

​He has wonderful days and then he has very dark days and Ive been able to talk him thru it most of the time. This past year tho, he has detriorated, its like hes losing the will to keep fighting and Im not getting thru to him like I used to be able to do. Hes angry and has gotten very verbally abusive which doesnt really "Hurt" because I know that he isnt normally like that, hes a very thoughtful and appreciative guy. I know its mostly the PTSD and dang, the guys been thru a lot and hes tired, but its happening more frequently now and its starting to get to me. I dont know what to do, anything positive I say he turns negative. I sometimes think hes trying to see if I tell him off so in his mind, if he gives up since Im "mad" at him, i wont be so hurt?  or something like that?  
​hes all over the place, one day hes happy and wants to do things, the next hes severely depressed and then the next hes paranoid that someone is watching him.  He gets confused and hes fallen and hasnt told me until days later. He knows I am especially touchy about that because my grampa fell down the stairs and died that night, still wont use his cane unless I nag him. 
​My main frustration is that there are things he can do to help himself and he just wont. An example being he has OCD and picks at himself when hes stressed ( totally grosses me out but I dont' want him to know and feel embarrased)  I know its 95% a compulsion and thats not his fault. That 5% percent tho, he can do but refuses. Ive suggested a glove, hold the remote in his hand, etc... I even got him a fidget cube and he wont use it.   things like that constantly and I am at a loss. 
​It is maddening to watch someone I care about go downhill and I cant help. I cant make him do anything and I wouldnt anyways.  Im finding myself starting to feel mad at him for not helping himself in the small ways he can. That makes me feel like crap because I shouldnt feel that way but I know I am overwhelemed and only human also.....

So, what do I do? ANY suggestions would help. ty!!!!