When it comes to who pays what, it really depends upon you both and what you both feel is good between you both. If you have been there for rent free, obviously he knows you make less etc. if he has a problem with that, then he would have said something from the start.
At this point, you're not married, so yes you are living there. If you both break up, you're not going to get anything out of the house as if you were married. So if he is fine with you staying there and not paying rent so to speak, then it's fine.
There are couples that the man pays for more, because he makes more. And the lady buys the foods, cooks, cleans along with buying laundry soap, bath soap etc. And then there are couples that pay everything 50/50.
So it's not really what someone else thinks is fair, it's what you and your boyfriend feel is fair. If you both have been living together all this time, the debt is still going to be there if you are married or not. If you both are serious, maybe you both can sit down and try and work together.. get the smallest bill and you both pay a little extra each month until it's paid off and work your way down until you get the bills caught up.
So although the advice you got from Mom and friends is good.. it's your life and you need to talk with your boyfriend and agree on this together. As you will be living in your situation every day, not them.
Hope this helps, and gives you some things to think about. If you need anything else please feel free to ask. If you found this helpful don't forget to click the *ACCEPT* button and please take a moment to leave me *POSITIVE* feedback.