Healer
"I know how I feel." "I know what I think." "I choose thoughts." I can do that without or with therapy, and still remain miserable. I can do that without meditation.

My understanding of 'meditation' is that once a person 'gets there' feelings & thoughts evaporate. Even the awareness of breathing, of being evaporates. So thoughts & feelings are completely suspended.

I asked Swami Poornamurti about 'disappearing,' being completely unaware of my own existence during a meditation session as if I'd just dissolved into the inner space. His comment was, "that happens sometimes, don't expect that to happen all the time." When I asked what should I study, what books should I read he simply said, "just do your practise."

Your comment, "I know how I feel, I know what I think, I choose thoughts" seems 'Cartesian to me. "I think therefore I am."

In the meditative state the lake of the mind eventually becomes still & calm & clear so there are no waves, no ripples, no disturbances, nor even feelings or thoughts.

Teachings of Swami Satyananda, volume 3, page 173 ..

"If you supress these [negative] thoughts, they return again to the depths of your unconscious mind where they play havoc. These subconscious impressions often cause introversion..."
On antar mouna p178 ... "This is a practice of seeing the mind, observing perceptions & accepting experiences... Be a silent, impartial witness to all the functions of the mind. Observe the part of the mind that thinks & the part which rejects thoughts....p178 "Millions of samskaras, latent impressions buried in the depths of the mind, are always coming up & influencing our behaviour, personality & destiny. ... close your eyes & be aware of what you are thinking."

It may be that you are aware of all of the above & more already & that you have been to many meditation retreats & workshops & so on. My comment then is that as the saying goes, 'you are what you eat, you are what you think.' There is no need to feel miserable. You have the power to change what you think, how you think & what you eat. You have the power to change where you live & who you associate with, what you do & how you think & feel about who you are. Cheers & Good Luck.