On a quick read, it sounds like half your family wants to run the property like a charity, and the other half (yours) does not.If were in your position, I would either want to buy the other side out, or get bought out.

Let them pay over time if necessary, or get a charity to bail them out. 

You seem to be operating a charity instead of a business.

Look You need to immediately change your mindset if you want to be successful in this business ...and This is a business not a charity .

Is there an extenuating circumstance that a charity may be able to help with?  

Run your business like a "business" and not a charity, you will sleep better at night.

Just food for thought, renting is a business relationship, not a charity.

I was happy to grant their request to terminate the lease early.Unless you're running a charity, stick to the plan and don't let emotions cloud your decisions.  

She is very sweet but seems to be running it more like a charity (no doubt there is much deferred maintenance on all the units).

Since I know you are making a profit on these deals, then you certainly bought them at or below 70% of market, unless you're in business as a charity for new investors (I doubt it).BTW, I almost never sell properties because I'm in the rental business.