Being sued for fraudulent Injuries in a car accident?

I need advice. My fiancé is being sued over an accident which happened 2 1/2 years ago over "severe Injuries which required medical attention" here's the problem. I showed up to this accident to get her car towed. My fiancé was working at Sonic, just got off of work, at a yielding turn, her foot slipped of the break, and she rear ended a guy in a rental car. When I showed up, the guy was perfectly fine, waking around talking to insurance people. Directly Infront of the cop, and me, and my fiancé, he told the cop that he was perfectly fine and required no medical attention. I checked, statue of limitations in Texas is 2 years, it was filed 1 day before the 2 years! What luck. Here's my main problem, my fiancé is currently taking care of her dying mother that has liver cancer, left side of her body is paralyzed from a stroke, and is bleeding from her brain, jaundice very bad, and problems go on and on. My fiancé is the 24/7 nurse, and is very stressed out, and crying all the time. Her mother is her best friend. This is the last thing that is needing to be done. We got served 3 days ago, but sense she wasn't home, and taking care of her mother at her house around the clock, and doesn't need to think about it, I told the server, that this is bad timing, and I will not give her the location due to her being overwhelmed with everything else. The b**** Ofcorse showed up to the moms house yesterday, and served her. I am very upset about this. I need to know what's going to happen? Her mother has a few days to a week left, and this just put the icing on the cake, she had a mental breakdown. I need to know what is going to happen about this, and if I can even sue the guy back for pain n suffering, fraudulent accusations, insurance fraud.... It what? I just don't want this guy to win due to it being a completely bullshit lawsuit. Please someone help me so I can stop worrying about it. Insurance has been contacted, but the papers have wrong information in it in the first place!