I'm so glad you are okay. I am sorry that your well-meaning friends have turned into consistent job applicants.
I agree with much of what Gamma G said - and it might be easier if you wrote a letter to each of these people (it can be largely the same letter, personalized based on what they did for you). The advantage of a letter is that you get to say everything you want to without being distracted or interrupted. And a personal thank you is the true sign of gratitude and great manners, so no one can fault you on it. In the letter, you might say any and all of the following as appropriate: "1) I want to take the time to thank you personally for all your support, 2) helping me with _____ (meals, driving kids, yard work, errands, whatever applies) was invaluable in allowing me to recover my strength so much more quickly than I could have imagined, 3) going through a life-threatening illness/surgery was so frightening and it was such a blessing to have so many friends giving to me and never expecting anything in return, which to me is the sign of true friendship, 4) losing time from our jobs/business was such a huge worry for my husband and me because of the incredible expenses of serious illness and medical care, so your generous offers of help have gone so far to help me get back on my feet, 5) now that I am healthy again, I truly relish every moment of doing the ordinary tasks of my life, from cooking to driving my children to their activities, so I happily decline your offers of help and trust that you understand I am grateful but can recover emotionally much faster if I can be self-sufficient, 6) thank you for continuing to call to offer to help, but please know that it's actually much better for me to keep focused on being healthy rather than face reminders of the danger I was in - it was such a painful time in so many ways and I'm sure you understand that I no longer want to revisit those feelings, 7) please believe me that I will always be grateful and I certainly know who to call if I ever need help again."
The advantage to that last line is it IMPLIES you will call them again, but in fact it really means to you that you know to call someone else!
If anyone pushes on the business things (hiring them), you can say that you're sure they understand why it's better to keep business and personal things separate, you need to have professional authority over those you hire, and so on. If they should ever say that you owe them, just pause, stare at them, and slowly say, "I thought you offered me so much help out of friendship. Are you saying you did it for your own advantage?" (Then do NOT fill the silence…let them sit there and sputter.) If you get any more offers of help, just refer to the letter and say, "As I said, I need to put that period in the past and focus on other things. Every weekly reminder of my illness is actually creating more pain for me."
Good luck with this! If you need help with a possible future surgery, try asking someone else, seeing if someone from your church or another organization can help you, or contacting a home health agency that provides everything from rides to appointments to cooking help to medical assistance. Around here, we pay $23 an hour for an agency to provide help - it might be easier than what you deal with when "friends" want payback.