Need help please

So my student loans are in default. They are roughly75k...I had no help from family funding my school and all I got out of it is a 35k a year job that I'm lucky to have. They are threatening to garnish my wages. I called trying to avoid that and they said the lowest possible payment I can make to be in the repair program would be 550$ a month. That's more than 25% of my income and way more than I can spend. This number is just based on my loan amount since they didn't even ask what . If I just let them garnish it will be roughly $320 a month which would be very hard on me but better than $550. What are the consequences for just letting them garnish as opposed to living in poverty for the repairment program? I feel like I need to quit my job and work under the table since I refuse to work everyday and be completely broke. Would they rather I pay no tax, use the ER as my doctor, and pay them nothing? I know I owe a lot but I don't make a lot either. When I told the rep this could leave me homeless and unable to pay anything he said that wasn't his problem. I'm also tired of being talked down to because I believed I needed a college degree and signed off on all this as a teenager.