Is this a legally binding agreement?

I took out a loan to replace my furnace when the old furnace went bad. I was paying off my loan when I lost my job due to lack of work and I am unable to make payments as agreed. I offered to make and have been making smaller payments and made the creditor aware I am selling my home to pay them and the mortgage both in full. They threatened to sue me but today I got a letter from the branch threatening to do the suing, saying I had been approved to borrow additional monies with no payments for two months. There are only 5 people in that office and they are computerized and can look up my account before they make these offers. I replied in writing with a payment for May declining the loan offer but thanking them for accepting my offer to make smaller payments by offering to lend me more money. Since they offered to make me another loan in writing knowing I could only pay partially, are they legally bound to accept the smaller payment on my current loan?