I would submit that those mind therapies, meditations, or exercises that are the most effective in generating new more functional behaviors are those that come close to resolving what we could call the category error (in the spirit of the philosophical term) in considering mind and brain. And, that error is to confuse a product with its source, the source being the fundamental impersonal downstairs machinery that generates the varieties of functional or dysfunctional selves that are its product, that we mistakenly imagine ourselves to be. Mental exercises like meditation permit the intuition of, perhaps come closest to, that more refined metacognitive underlying generative space that permits viewing of, and choice between, more or less functional self options.
A less wordy, maybe more useful, way of putting this is to say that third person introspection, viewing yourself as if looking at another actor, and placing this a historical story line, is more useful than immersed rumination (coulda, shoulda, woulda). It is the difference between residing mainly in the attentional versus default modes of cognition.
If there is a practical take-home message, it is that maintaining awareness of, and exercising, focused upstairs frontal attentional mechanisms is important to mental vitality and longevity. Such awareness is central in resisting the attacks on our attentional competence that comes from the confusing media jungle that tempts our passive default mode receptivity and reactivity.