Defile my life
There are a number of things that could be defiling his life.
1) Having to deal with not necessarily Jesse himself, but all the effects of it (having to explain to the other children that “the retard” they were wondering about is his brother, losing his childhood, etc.)
2) His parents (rather father and stepmothers) divorce ruining his childhood
3) Life itself ruining his life (if that makes sense). To
Rephrase it: the hardships of life defiling his life
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