What exactly are you concerned about? Are your grafts having problems?
If you want to be there for your young family, you need to change your outlook and
stop worrying. I know it's easier said than done, but it's something you have to try and do. Even if you need to open up and chat, get on here and post how you feel, we will understand and help. You are not alone, there are millions like us. Most bypasses last
the rest of a persons natural life, especially as they now use Arteries from the chest. If these get problems, they can also be stented. You are a long way off giving up.