I know how you feel. My closest friend was diagnosed with grade 4 brain cancer right when we were out of high school. For a while he only told me and his immediate family, since he also didn't want anyone to worry about it. It totally destroyed me and now he is off at college so I've seen him once since he left.

You probably have better answers than I do on how to be with him or support him at this time. But I do want to mention that you should remember to take care of yourself too. Talking to people about it like friends, family, or even a post will help.

I wish there was some easy answer or words of advice for what to do in this situation but I don't have any. It comes out of no where and can be overwhelming. It won't be easy but I wish you and your boyfriend the best. Take care.