Stray cat died and I feel terribly guilty

I was feeding a stray cat by house for many years (around 8).  For the last few months, I noticed he had a wound on his side.  He has had these before and they always seemed to heal fine but this one was lingering.  He was hard to approach, wouldn't really let me pet him or get too close to him.  I actually got antibiotics from a vet and I gave him those and the wound look like it was improving.  Last week before I was leaving for the shore, he was on my deck and looked really hot, even panting.  Well, I grabbed him with a towel and set up a place in my basement - i figured he at least was out of the heat.  He was eating fine and he drank water that day.  My son fed him and gave him water everyday and he seemed fine, the wound looked better.  My plan was to finally try to get him to the vet when I got home in 5 days.  Well, the day before i returned, my son called my hysterical (my son is 21 years old) and told my that our cat "Dickie" had died.   Well, now I am wracked with guilt that I didn't do more for him or try harder - I even think I should have tried to bring him in years ago but I already had 5 cats in my house and he never seemed like he wanted to be inside.  He lived in my garage for the most part - he would go in through a small window.  I can't stop beating myself up that I should have done more to help him

You can't beat yourself up. We do the best we can for these guys and, hopefully, learn from each experience. If not for your care over the last 8 yrs, he would have had no one. He knows you loved him and were trying to care for him, otherwise , he would have moved on. Feel comfort in knowing that you gave him food, shelter, and companionship, even if it was on his terms. You did try, giving him antibiotics and bringing him in. It is heartbreaking that they won't fully give in and trust us. He had a better life with you in it. God bless and rest in peace Dickie.

I'm so sorry for your loss. If you kitty lived his entire life outdoors and had frequent infections, it's possible he may have had an underlying disease.  Eight years is a long life for an outdoor only cat, and you took care of him and gave him his freedom and a comfortable life, and I'm sure he loved and appreciated you.  He passed peacefully inside with your family, knowing he was loved.       

If he regularly had wounds like that, he clearly was not trapped and neutered ever, so he was fighting with other unfixed males.

Very sad, sorry he died, let go of the guilt, they are all lessons learned.

Nobody does all just right, or has hindsight. 

You could not have known.

You did everything you could - - and take comfort that you showed him more kindness than anyone else  had in probably ages (or perhaps his whole life).