舍不得 is the negative potential form: 舍 (to give up) + 不得 (cannot). Its opposite is 舍得 (willing to part with). The pattern is: 舍不得 + verb/noun.
culture
The proverb 舍不得孩子套不着狼 is a vivid Chinese saying: you must be willing to sacrifice something precious to achieve a big goal. Similar to 'nothing ventured, nothing gained.'