TLDR: My dad has hid his medical issues for years and I have to brow beat him for any info. Found out he has major skin cancer. He told mother not to tell me. I'm extremely upset and frustrated and haven't said anything.

My mother and father have been divorced since I was 13. It was a good thing. My little sister died a few years before due to an accident and they never could recover. But, my mom moved us to Michigan with her (whole other rant) and he stayed in Florida. 

My father was always a happy going guy, but got hooked on opioids and ruined his life for a long time. He turned bitter and extremely sarcastic and moody. Eventually hurt me so bad I cut contact until I was 18. Now, we have a decent relationship and talk about once every two weeks. But he's still gruff and sarcastic, I just know how to roll with the punches better. He's constantly working and I'm planning a wedding and finding a new job. So we dont talk a ton. Mostly "Hi, how are you?" And ask about each other. 

A few years back I found out he was hiding his COPD from me (he left his medication on the bathroom sink on accident one time and I knew what it was), which my grandfather (his father) had recently died from. I tried to talk to him about it and he keeps everything really vague and changes the subject. I know why, and I dont know if I'd have the strength to tell my kids either. But he would rather ignore the illness than take the treatments correctly. Which is frustrating because my mom, who is a resperatory therapist, has taught him how over and over again every Christmas he comes up. This year, he looked worse than ever... and had a huge bandaid on his face. He said he got cut at work and I let it go. Today, however, I found out he has skin cancer. My mom accidentally flashed the message to me rather than a picture she thought she was showing me. She starts profusely apologizing and saying I wasn't supposed to know and that I can't say anything.

I'm incredibly and selfishly hurt. He's dying. The treatments for his cancer aren't working and he's keeping it pretty vague with her too when she came clean after the discovery. He says he wants to make it to my wedding May 2020 and he can't die before then... I want to help so bad. Fly down and live with him to make sure he's taking his medication, make sure he's going to all his treatments, make sure he's eating... he taught me how to walk for fucks sake... but I know if he knows I found out, he'd be devistated and would retreat even further... I don't think he'd tell me about it on his own, as he never told me about the COPD that he apparently had for years... I'm terrified for him... I know I'm not his mom. But I love him and don't know what to do or how to handle it... 

I feel like an asshole because I just want to call him and yell... I'm mad at him and idk if its selfish and I feel like such an asshole... I haven't called, because I know he doesn't want me to know.