To me people advising you to go to university/study/get a better job/it's not too late etc are like a modern day version of the fable about two fishermen...
Question: "Why don't you go to university for 4 years, struggle with childcare, study in the evenings, get a long hours well paid job, pay for childcare, work into the evenings, buy a bigger house, pay a bigger mortgage, take regular holidays abroad.....
and what would you like to do when you have made it and are ready to retire OP?"
OP Answer: "Oh I don't know probably buy a little cottage in the peak district and live a quiet life with my dog."
The OP is happy as she is. So she is already living the dream. Not everyone wants to be pelting full speed on the capitalist hamster wheel.
To help your daughter if she wants to go to uni OP I would suggest, as the easiest time to work more is when your daughter is an adult, that you up your hours or get a second job at that point. Whatever extra you can bring home you can give to her.
You could also encourage your daughter to take a year out before uni. She can work and save a nest egg to take, and as she will be an adult you can up your hours and start saving more - as well as securing that increased monthly income to help her when she is away at uni.
When your daughter graduates you can reduce your hours again if you want to, or keep them higher to add to your savings or to help your daughter further.
Your life sounds great to me.