Burnout

I think I may be able to see the point where I genuinely can't do this job any more.  And it's a shame, because I need a job, but part of this has become too much to bear.

The specific issue is this.  The client has a lot of responses to agitation, but among the most common are self hitting and aggressively picking at scabs.  As a result of this he has a large number of slowly migrating scabs and bruises that move around but never go away.  The problem is that when he spends 12 hours hurting himself there's nothing I can do to stop him.  I can't really communicate with him, I can't restrain or tranquilize him, and most of his sources of agitation can't be helped either.  What it amounts to is a lot of time watching someone hurt themselves and being powerless to stop it. 

And it's too much.  It hurts me, because I care about him, I'm trying to help him, and he only gets worse and will never get better.  I know this, and I know that it's only a few months, maybe a few weeks, before I just stop caring.  I don't know how long it is between that and active resent, but I know that's where it leads.

Right now I'm really not sure what to do about this.  I just know that this job's days are numbered.