Detachment is a lot of trial and error at first.
It's about not making their issue, little snit, insecurity, dramatic mood shift about you, not letting these dips and rises dictate how your day is progressing.
At first, I only detached from the bad or sad stuff, only to realize, it's important to observe and note that when the A is on a good tip, that that, too can be an erratic swing.
I have kind of learned not to hang my hat on his conclusions, his pity party's. Or his expressions of extreme love and clarity.
If it sounds crazy, it is. Excusing yourself from a pity soaked phone call because your day is going well is a bit of detaching.
Not letting yourself think she's finally got it totally together because she calls and says she had a big realization is another bit of detachment. I say," that's great! I'm so happy for you!" but, I'm not going to book a family vacation to celebrate, because in a few days, the A may shift back, or full on deny the progress.
It's a balancing act of love support for the other and self preservation/ self care.
Loving someone who is ill w alcoholism does not need to mean misery or guilt or discomfort for you.