One definition for relapse is:
a deterioration in someone's state of health after a temporary improvement

The definition does not suggest anything about the cause or whether or not a person's life choices were to blame. So for instance we could say a person has a relapse of a particular cancer after a period of remission. That would not necessarily mean the person is at fault or chose additional symptoms.

I realize perhaps the term relapse carries a stigma, but it shouldn't. It is a valid description in some cases. I am sure there are better terms to use, but it doesn't offend me. My IOP therapist called it relapse and I got used to it I guess. She didn't use the term to specifically label incidences where a person's choices led them to returned symptoms.