Sorting out what are the 'you' parts, and what are the 'them' parts - in terms of where the strain is affecting you.
I have a work friend who stresses me out, except I also do like having a more friendly connection with them, because they aren't fully and completely stressful to me. I had to separate what in their actions/behaviors did I need to practice accepting (and therefore not judging or being bothered by), and what else (besides lack of acceptance) was in my own behavior/thoughts that might be causing me to get stressed.
Finally, there was identifying how and when I wanted to address things that they did that I did not want to just accept; things that I hoped they would engage in a dialogue with me about, in terms of our relationship - and vice-versa, opening the door for them to talk with me about things I might be doing that stressed them.
It's hard with interpersonal stuff sometimes: whoever knows more about how to shift thoughts (CBT/general therapy stuff) is likely to end up making more adjustments almost by default. However, the biggest adjustment (usually) comes in applying non-judgement and mindfulness/acceptance.
And that stuff, we all benefit from practicing, I believe. No limits on its usefulness.
I've learned to break off relationships simply by realizing how much work it was for me to continually accept behavior that i really, actually, believed I could not accept. For me, that was destructive addiction and fundamental differences in ethics. Life's too short, I don't want to manage those relationships.
But, person I genuinely like who just has a frustrating habit of never picking up the tab? Worth the effort to work it through for myself and figure out what I actually want to say and how we might fix it. And that they wanted to tell me that they had a hard time with certain profanities I used? I was actually glad to know, and not a problem for me to adjust.
