I think your heart seems to be paved with good intentions. You know what they say about roads to hell though ?
When you dicuss the fact that, their energies and attitudes are affecting the group,..You now understand why some companies have a 'don`t date a employee' type of policy in place.
If you want to NOT stand in judgement, then you need to pull yourself OUT of that specific situation, and sit down with your fellow leaders and members and discuss some policies for the future. Maybe dating within the group is ok, and fine, but you make up and hand out guidelines, for how to handle social interactions within the group/church after relationships go awry.
Specifically mention what the group will and wont tolerate, where to go to for help, and venting, what the group can do to help reduce stressors, etc.
Said hand-out needs to explain the type of stress put upon the group, when there is negative energies in the room.
When people are in pain from relationship-breakdown, they dont see very clearly, they don`t see past their own pain. A guideline would help negotiate this while someone is flopping through their misery.
Do you think, maybe, that the info that was told to your sick/surgery-induced friend, is actually the source of your hurt ? You could be upset that someone you care about, had enough going on, without bullshit drama being laid at his feet.
It might be prompting you to not see clearly, how you need to stay OUT of this dynamic.
While you mean well, your own words ( even if you dont think you communicate clearly,..I can tell you, you are communicating your feelings very clear. Your 'lack' is only in being vague initially.) tells me, that you have far to much info about this situation, and feel some need to 'deal' with it.
If I were you, I`d redirect that energy towards future ways for your group to deal with such situations, and forget judging your friends in their current situation.
They got themselves into it, let them get themselves out of it.