this link expresses the difference and similarities between empathy and compassion.
"empathy emphasises feeling and emotion while with compassion the emphasis is more on action. I think we could say that empathy can embrace listening but not going on a street march. Compassion I think is readily compatible with street marches and other forms of organisation too.
It seems to me that empathy is a kind of receptivity while compassion adds an element of doing. We may have empathy for someone’s situation without doing anything about it. I don’t think we could say we are compassionate and do nothing. I think compassion may be the slightly larger concept.
The overlaps that I see are to do with our feelings and motivation. Both empathy and compassion are an openness to the other person, their feelings and situation. With both empathy and compassion we are “moved” – we respond to the other person’s feelings and situation. I think empathy is more the response to the person’s feelings and emotions while compassion is more the response to their situation."
I think in terms for what you are talking about the action would be, for example, taking care of things that he can not right now, forgiving his attitude and hurtful snappy words because you know he is hurt, remaining cheery and planning fun stuff to do so he won't get too down... possibly trying to solve the situation by contacting the person that is causing the hurt and trying to get them to change their mind....
Not to say that this is what is going on for you, but as an example of compassion that perhaps fits similarly to what you are saying and what your situation is. This is a close example to the compassion I have had in the past when PN has been hurting because a struggle he has had with love.