My mother apparently stopped drinking several years ago, but it is the only thing in her life that has changed. She still lives alone in a mostly-empty house, rarely gets off the couch, watches television, and naps her days away. She may be sober, but she never sought recovery.
Other members of my family have turned themselves inside-out in an effort to break her of this sad cycle, to move her closer to family, to make a better life for her, and she has resisted and refused all efforts. I used to call every now and then, but our conversations were so uncomfortable for her she couldn't stand to talk for more than five minutes, and even these bare interactions would leave me feeling sad for days.
Eventually I let her go. She knows how to contact me, if she chooses to. My life is more peaceful now.
She also knows that there are literally hundreds of ways she could change her life. She chooses not to pursue them, much to the chagrin of the rest of the family. Should we all limit ourselves to the same choices, because she does? Why?
Other people have the right to live exactly as they choose. Why would you feel guilty living yours the way you choose? Instead of indulging in useless guilt, be grateful you are not afflicted with addiction, that you have the freedom and means to pursue your interests and pleasures -- so many others do not. Guilt is the difference between what is real and what you wish was real, and it doesn't do you or your brother any good.