Deliquent private student loans

My student loans went into default some time ago. My federal loans were rehabed and are now in good standing and I was able to defer them for a little while. My private loans are still in default. They've been in default for some time and I don't know how to approach it or the collectors. They have no obligation to help and don't have any rehab programs like the federal loans. I want to pay, but I can't afford to pay what I owe at once, so what do I do? At this point, I don't even bother with my FICO, my credit is destroyed. I've learned to accept it, but I do want to begin handling this debt. Any suggestions?