Please, Please, Please, I beg you Please stop feeling guilty. I completely understand exactly how you feel because I went through the same thing with my baby. We spent over $4000 on my Halfie. Before my husband turned to me and said we can't keep doing this........My Halfie was also so sick it was just a matter of time. I finally realized that spending the money was more selfish than anything else. We were spending it for us not for halfie. All we were doing was prolonging the inevitable. Susan in hindsight I wish I would have done what you did. I should have let her go after the 2nd visit to the vet, after the oxygen tank and meds. Yes my baby did die in my arms, but I just wish I hadn't let her suffer for so long before she passed. That was needless! I did have the last minutes to let her know how much I loved her and I'm grateful for that. But what you did was right!
When God entrusts these creatures to us he's full aware of what our capabilities are, Mentally, emotionally and monetarily. If Shultzi wasn't meant to be yours he wouldn't have been. If God hadn't thought you were the best owner possible for Shultzi, he wouldn't have given him to you in the first place. You did nothing wrong! You gave your baby the best life possible while you had him. That's all god expected of you and that's all Shultzi needed.