Dear Eric >> I am 57, and I am the fourth of five siblings. My adolescent years were marked by loneliness, fear, bullying from others because of my weight and anxiety. I had no outlet to express myself so I either over ate or took out my rage on my younger sister.

When I grew up, I would often ruminate over how badly I treated my sister in my teen years. My sister coped with her issues, which are also numerous, by getting involved in the drug world as a teen. At age 55 she is still an incredibly sick, active addict despite many attempts at rehab.

I’ve reached out to my sister to apologize for the way I treated her, asking for forgiveness, and promising to do better.

I constantly worry about her to the point where it would make me physically ill, and my husband became worried that my obsession with “helping” to fix my sister’s problems was affecting me mentally and physically.

After many years of therapy, I know that this obsession with helping to fix her problems and be involved was all about me believing that I am responsible for how my sister turned out and I know now, intellectually, that it’s a lot more complex than that.

Yet I live with this impossible dread that I get to have all of this comfort, and my sister doesn’t and it’s not fair that I was so mean to her and possibly ruined her life. What if she was so traumatized by the mean sibling that she turned to drugs to self-medicate? How do I reconcile with all of this?

— Guilty Sister

Dear Sister >> Your attention is focused on your sister, but I think you’re really angry with yourself and the obsession is a reaction to feeling powerless, just as it was in adolescence.

Hopefully your therapist has told you the following, but it bears repeating: You did not have the power to make your sister a person who struggles with substances. Guilt and shame feed on anything they can get their hands on. But, by your account, your sister also had other issues to overcome beyond the way you treated her.

Grant yourself some grace — the thought process you’re stuck in is the product of decades of trauma, external and internal. Every time it comes up, label it for what it is: your brain’s way of torturing you for something you can’t control.

Ask yourself what it would take to forgive yourself for your past actions, to see yourself as someone who needed help and didn’t get it, and someone, like your sister, who was trapped in an imperfect family system.

Send questions to R. Eric Thomas at eric@askingeric.com