At present, it sounds like you are already doing what you need to ("practicing scales and basic Hanon") under the circumstances; if the merits of Hanon are otherwise debatable, many of us who've been away from piano for long periods of time have found it useful for shaking the rust off the fingers.
You should be assured, though, that six months without playing really isn't a long time. Even after years (or decades!), people typically regain their previous proficiency level reasonably quickly and without much difficulty unless illness, injury or age-related infirmity are a factor.
If not having access to piano "books" means the scores of music you've learned in the past,
that's a problem. Fortunately, non-copyrighted scores are freely available online;
IMSLP/Petrucci Library is the biggest resource, with most music by most composers from the common practice period on hand (though not necessarily the editions one would choose for oneself). Doesn't your Gold membership here give you access to an on-site printable sheet music library as well?
Plenty of people continue to learn without teachers, so don't be afraid to give it a shot. Avail yourself of YouTube and IMSLP to listen to lots of piano music; choose pieces at or somewhat above your skill level that you love and are convinced you'll have the motivation to teach yourself.
Best wishes with your endeavor, but don't despair that
not practicing means you'll forget how to play. It's not quite like swimming or riding a bicycle, but there's no reason to think you couldn't go years without it and still be back in the saddle in a matter of weeks.
Topic: Returning to the Piano