I feel like a failure

I had depression during my pregnancy, I had an emergency C-section after a failed induction and I had PPD and PPA as soon as I left the hospital, I chose not to breast feed because I was already struggling. My son has asthma and a very poor immune system and I feel like it’s my fault because I didn’t breastfeed, my milk came in and I chose to not give it to him and now my husband thinks he’s sick because of me not breastfeeding and I feel horrible, maybe I could have prevented him from struggling with asthma and allergies?