I've thrifted most of my wardrobe for years, but my teenager insists on buying fast fashion every month—she says secondhand feels 'old' even when it's trendy. She spends $40 on five shirts that fall apart in three washes, whereas my $15 thrifted jeans have lasted a decade. Should we push young people to buy less and mend more, or is that just my generation's nostalgia talking?