They were used to you being helpful - or rather, useful. So they were willing to pretend they loved you - as long as they could use you.
Years into this arrangement, you got sick, real sick. At first they pitied you. But then you didn't die.
You couldn't help them get whatever they wanted anymore, so obviously, they lost interest in you. You kept trying, not because you needed them to care, simply because you genuinely liked to give people a hand, make them benefit from your knowledge and your contacts. It didn't work - you were not the same person anymore, never going to be again. And they got mad at you. I mean, seriously, dude, either you died, either you were useful. Otherwise they didn't care; otherwise they didn't know how to handle you.
They didn't wanna hear about the shit you were going through - they didn't give a flying fuck about surgery, about physio, about chemo, about medication, about pain, about radio. They wished you dealt with your shit on your own. They hoped to be able to keep their distance, whatever help they offered, they offered very quickly, and prayed to god you wouldn't accept.
They felt uneasy. Never mind that you were the one in pain, depressed, scared. They'd rather retreat to their comfort zone.
There was nothing good to suck out of you anymore, and they thought, now that's really a shame.