A year ago, I (25M) was diagnosed with limb-onset ALS after a long struggle with experiencing foot drop and muscle weakness. For a few months, I hid my diagnosis from everyone until progression of the disease forced me to come clean. To be honest I'm still coming to terms with this and each day has been a living hell as I wake up not knowing what motor skills I will lose next. I have always been fiercely independent and the protector of the people I love, so it kills me knowing that everyone who loves me (my girlfriend especially) now has to bear the burden of my illness. The one person I haven't told is my grandpa, who raised me and my brother until we were teens because my parents were at work all the time. He's the one cared for me the most, who has literally watched me grow up. I have always promised to take care of and give him the best of everything because he sacrificed to give me as much of a happy childhood as he could. Ever since I was diagnosed the thought of having to tell my grandpa that his grandson has an incurable, degenerative disease has plagued me and I don't think I can gather up the courage to tell him or to face the fact that I can't fulfill my promise. He's nearing 70 and I want him to live as happily as possible without worrying about me. The other day, we met for a family dinner. I don't see my grandpa very often now, so before the dinner I was adamant that my grandpa would not find out. My brother and girlfriend agreed to cover for me using a wheelchair by saying I'd been injured playing soccer. Grandpa accepted the excuse and all seemed to be well until my cousin, who wasn't aware my grandpa didn't know, brought it up. As I expected, he was devastated and couldn't stop asking me why I didn't tell him. Later that night, the sudden emotional shock likely triggered his heart condition (he has a history of heart attacks). My grandpa is now in the hospital and I haven't been able to stop crying. My brother is furious at my cousin for revealing my diagnosis and even more so for not being apologetic since she's insisting that it's my fault because I should have just been honest with my grandpa. She called me manipulative and a liar and said that it wasn't my place to decide whether grandpa could handle it or not. The guilt is eating me alive, but at the same time the aftermath just tells me that I was right to hide it because the news absolutely crushed my grandpa. I don't know what to do anymore except to pray that my grandpa makes it through. AITA?