Vet bills for our Lacey girl

We adopted Lacey just over a year ago. 
She was rescued along with several others that had been abandoned. She was extremely malnourished, never loved, or hadn’t even step foot into a house. 
We took her in knowing this, nervous of what kind of dog she would be in our family given her history. Come to find out, she was everything we wanted and more!!!! She is the most loving, sweet, snuggly dog. 
When we rescued her we were told that she had been negative for heartworm, all heart issues and only needed 6 months of preventive heartworm care, which we did... fast forward to last week....
Lacey started coughing very seldom and randomly. Her mood and energy never changed, we watched her carefully and the cough seemed to die down. This morning when we got up, I noticed she was having difficulty breathing. We rushed her to the vets.
There, she spent several hours in the oxygen kennel while waiting for blood, urine and X-ray results to come in. The findings were not as we had hoped. She has heartworm which led to bronchitis and secondary phnemonia. They also found a heart defect and that her heart is enlarged, which we had no idea about. 
Lacey has an extremely long, painful, expensive road ahead of her. The vet is confident and optimistic with a full recovery. The downfall, is that it’s not cheap. 
My husband is currently out of work, and does not have a start date until his injury is healed and my income during the summer is limited. 
Todays bill was just shy of $900 which my parents gracially loaned us and we need another $1200 to continue the treatment. 
We are not ones to ask for help. But, under these circumstances we feel that it’s time to ask. Any little bit will help our girl! 
Thank you in advance!!! Leann, Joe, Jace and Lacey