What is something that happened you initially thought was bad but ended up being grateful for and saw as very positive?

Last year my yearly medical checkup results indicated that I have a tumor. After a couple of months of stressing and additional tests, it ended up as being a false alarm. This was one of the best things that happened to me in a long time, it gave me a good kick in the ass to start working on myself and my mental health. I started seeing a counsellor, started to travel abroad for vacation twice per year, stopped stressing so much amout my job, etc..