invisible
Home Economics didn't cover mending and darning for us, and asking any of us to do any sewing besides buttons by hand probably would have had the class bursting out in laughter.
re-weaving
Yes, and that is part of the reason such places, along with things like good French hand laundries are going by the boards. It takes tremendous effort and talent to produce good results, and people have to make a living so the era of finding seduced and abandoned girls, or widows willing to take in mending or such work to make ends met are long over.
Besides that, hardly anyone mends or darns anything today, even cashmere sweaters costing hundreds of dollars. People seem to just wear something to death, then chuck it into the rubbish.