Agree with you that it is critical to be circumspect about how and with whom we choose to spend our time. It helps us be resilient in difficult interactions, while also helping us to prioritize the many claims upon our time.

One of the trickiest challenges I've found is identifying activities I do resentfully out of a vague sense of obligation. After facing the fact I feel obliged and resentful, I've often found ways to reach a better outcome for both myself and other parties involved by understanding and advocating for my interests in a constructive way.

If you haven't already, you may want to check out negotiation literature (i.e. Getting to Yes and Difficult Conversations) for more tips on defining and championing your interests… Provided you feel this is a valuable way to spend your time