I can share a similar experience, and the outcome may provide comfort for the OP. My SO of approx 2 years moved into my house (about 12 years after I bought it). I was comfortably employed making approximately 2x his salary. I never expected him to cover half the home’s expenses, but he has made life in our house a home in many ways.
Like OP’s SO, my SO did not come from a family with financial discipline. Over time, I have, I think, given valuable lessons (most learned here) to my SO, and he has paid off his car (and not run out to buy a new one because he had ‘extra’ cash in his pocket), paid down his CC bills, added to his 401k, etc. This did not happen overnight, but I believe I’ve instilled in him the value of saving.
I don’t cook; he loves to cook. He loves food shopping (and pays for it). I detest it. I maintain virtually every mechanical system in the house; he cleans the house and mows the lawn and does the laundry. He pays the internet/cable/phone bill.
Eighteen years later, the mortgage is paid off (early). I retired (early) and my partner still cooks, shops, cleans, mows, and works. It works for us. At this point, I’m planning to add his name to the deed.
We travel several times a year, and I pay twice as much as he. Just because I have it. It’s normal for us and never causes even an inkling of an issue.
A relationship is many things, including arrangements as mundane as these. But in the end, only you can decide if these concessions/trade-offs/arrangements make you happy. A relationship is not always about money. If you gel together and see beyond his current student loan debt to a period when he can be/will be financially responsible and independent, then don’t end your relationship for these temporary conditions.