Some of this is just common sense. There is no good cancer so that gets me the most anyone that would say that. And no one can know how someone else feels unless they have the same thing but even then we are all different on how we handle things, what affects us, what make us sad, happy, what words we would rather hear
When my husband was going through cancer as long as friends meant well he didn't expect them to always say the right thing. He rather have someone that really cares about him and what he is going through (same with me) than someone that always has the correct words but doesn't bother to visit like they did before or bother to see if we need anything.
Most of our friends now have passed away or moved away with no Internet to stay in touch. Having geniune friends that care about us has meant everything with what we have been through. I have friends that tell me how strong I am when I know I am not strong! I am just surviving LOL doing what i have to but I know they love me and care about what I am going through so that means more to me than if they chose their words perfectly. Now when someone is not a genuine friend, doesn't really care how we are and they say the wrong thing to me then that would upset me. I Keep in mind everyone is different so different things will bother different people and that could leave some really caring people thinking they just rather not say anything to us than to say the wrong thing. I wouldn't want someone that really cares about us to not come by because they were afraid they would say the wrong thing.
If someone has an easy life, no health problems, finanically secure, loving family to help out, then when they say they know how we feel or to stay positive or how strong I am, those people are the ones that it gets me when they say things like that to me but when my friends that have gone through bad times and/or has severe physical problems even if not the same as my husband and I have gone through then I know their words come from their heart even if they were not the words I rather hear it doesn't bother me. Just them being here for me means everything.