The human body is a miracle! If you quit drinking now, the quality of your health will change dramatically & you don't need to walk in fear.
It is hard to consider if you think it is a choice between valued friendships & alcohol. Humans are social creatures! Nobody wants to lock themselves away & get healthy all alone.
Take small steps. Try a night where you go hang out after work & don't drink. Just consider everything a fascinating experiment! It actually is fascinating!
I just turned 50. I want to be healthy & strong for many more years! I have to be healthy & strong to continue working, or my life will be just work & resting to be strong enough to work. That is a lonely life. That was my mother's life for her last ten years (she was an alcoholic).
58 is not too old. But an active alcoholic at 58 is pushing their edge.
Start with one night free of alcohol, then two, then three. I believe you will start to see changes in how you feel, & will want to go further.
Start committing to some activities that are not about drinking. Make just one or two new friends with whom you do not drink.
I met friends who don't drink at AA, & - frankly - they put true energy into friendship & have become very important to me!
The physical symptoms you describe are concerning. Listen to your body! It really wants to be strong.