I can sympathise. My hubby is just finishing his 4th year of a biology degree and will potentially be going on to do his PGCE (although his enthusiasm has waned slightly as he hates studying! lol) and it's taken a lot out of us with the sacrifices we've made, the compromises, the house moves and the adjustment financially.
I would probably try to get him to see this as a family venture - life I mean - it's not a solo venture and he needs to see his family unit as his support network, not as an inconvenience. I've had to point this out to hubby on many an occasion, not least last week when he was telling me he didn't want to go to his own graduation! How selfish! lol
Could he defer by a year, and maybe save up for his tuition so you didn't need to get a loan? in the meantime could he maybe do the necessary A Levels via OU or through the local college so maybe he could do it closer to home? Or use the time to gain work experience which may also help him. Academics can only get one so far. This would also give you time to fulfil your own ambitions and emotional needs, like completing your family and so on.
This is a team effort, or it should be anyway, and if you can view it that way, it makes the whole thing a lot easier. I also agree with MarineWAG though that it's important that everyone gets a crack of the whip, and that a move isn't always a bad thing - nothing ventured, nothing gained!
Good luck x