Why does Miss Havisham raise Estella as she does?

Miss Havisham raises Estella to avenge her own betrayal — to wound men as she was wounded. Estella is trained in beauty without tenderness, and Pip is invited to Satis House partly as a live demonstration of that training. The project is intimate and systematic: clocks stopped, wedding dress worn as costume, girls’ hearts treated as instruments.

Dickens does not let Miss Havisham remain purely monstrous. Late scenes force her to see what she has made, and Pip’s forgiveness is hard-earned rather than automatic. Still, the harm to Estella and to Pip is real. The concept of instrumental love is the longer answer; this question is the entry point.