But holding to the tangible:
There are three things that we need to succeed as individuals. The first, obviously, is health, which is the organic capacity to channel physical energy. The second is happiness, which is a balance of the mind that sustains our will. Finally, we have ability - knowledge and skills that allow us to generate and sustain value in our relationships with others, and therefore to lay claim to their capacity to generate value.
We can't expect to have all three of these all of the time. Ability develops under stress, and unless pushed to the point of failure never reaches its limits. This can have consequences for both our physical and mental health, at least in the short term. In general, though, the aphorism holds: "What doesn't kill you makes you stronger." And that strength allows us to do for ourselves, as well as others.
By implication, loving ourselves means hewing to the road of greater ability for much of our lives. It is not the soft cotton candy of indulgence. It is the pursuit of excellence, in whatever form we can attain it.
Moving forward in that way is an important part of loving others. The more powerful we are, the more they may gain power through their association with us. Among the important questions we must ask ourselves in evaluating our relationships is: "Am I more powerful now than I was before? If not, why not? Am I making an investment in someone else? Do I feel confident that that investment will be reciprocated later on?" If not, we must be loath to betray the confidence of our other colleagues by allowing ourselves to be weakened by a selfish personality.