It really depends.
Some people will basically shun anyone who they perceive of as being weak. Others will always at least be friendly.
Some will moderate their behaviour towards you based on what they think or know you to be doing in your life. If you are keeping very quiet, not doing things that might get you DFed then they might treat you better than if the opposite is true.
If they are family or former close friends then they may behave differently to others.
I think the worst is becoming known as someone with a gripe. That really does get you marked out to be avoided and, of course, you don't actually have to be moaning about anything at all. Simply asking a question or raised a point of criticism can be enough. They simply cannot cope with someone even very quietly simply saying "I don't accept this as a The Truth any more". It has to become something based around bitterness and complaint.
Illness or work dragging you away is OK but logical thought is not.