These tenants did not respond to ~80% of our communication, and the rest they maybe responded to 1-2 weeks later.Long story short, I got partial rent for October and no rent for December.

That would have been clearly communicated through disclosures in your loan documents that you signed.

Otherwise a simple LLC with two partners wherein the operating agreement spells out these same things may work well.The key here is to communicated exhaustively about the "what ifs" and "who does what and when" and "if you drop dead, what do I do", etc. 

Just make sure you have a good line of communication with the residents(just don't treat them like a friend).

The lender was just from me and my partner calling as many community banks in the area as we could find and asking them if they have worked with out of state investors, and also telling them our goals and strategy. we found one that we really like and have been in constant communication with him the whole way. the final step for us was to go to Indiana and meet with our team, take them all out to lunch/dinner, and get to know them on a more personal basis and motivate them to work hard with us and for us, that we werent a flash in the pan investor group, and we were in it for the long haul and really believed in our system and market. we also jumped on one of the first deals he brought us to show him we werent joking around. we made it happen and our deal finder got his cut and everyone was happy :). 

Her only means of communication up to this point (6 months later) has been via text.  

If possible, try to politely communicate to defuse the current situation showing dignity and respect (if you both are calling the cops, it may be too late).

The agent doesn't know how to communicate and acts too busy to be bothered.

It's really going to come down to what was communicated, preferably in writing, and then what transpired after you gave the initial approval. 

I have loans with all of them currently and have been very pleased with their terms and communication.