Basic Training is Necessary Before Going into Battle

If you want to be able to employ basic breathing techniques when you need it, it has to be second-nature to you. One does not expect to behave as a martial artist when the occasion arises, if one has never practiced martial arts techniques in a dojo beforehand. One does not go into battle if one has never practiced fighting techniques, or breaking down and repairing a rifle in seconds, in the dark, in case your weapon jams in a fire-fight. 

Before one learns to balance on a bicycle, most children use training wheels which initially gives a 3-point stable position on the ground. Then, the wheels are raised incrementally. One learns to balance oneself on the bike without fear of toppling to the ground. With the training wheels an inch or so above the ground, there is just some wobble until balance becomes natural.

If you want to utilize classic breathing techniques in order to establish emotional balance, you need to practice before the need arises in a crisis. This is what sitting meditation is for. One practices sitting, often in a 3-point sitting posture (knees and butt), in a stable posture. One works with breath until unwanted thoughts evaporate, and consequently, with disturbing thoughts gone, there is nothing left for negative emotions to arise in reaction to. I think it is entirely unrealistic to expect meditative equipoise to arise when needed, if one is hardly acquainted with the state of mind. Therefore, it seems incumbent upon you to find a style of meditation with a proven history, that appeals to you, in order to accustom yourself to those states so that they are available to you when you need them. There are then other applications for the state of mind, say, waiting in a boring line, instead of indulging in cell phone addictive behavior. For meditators, meditation colors one's whole life if one wants it to, and it engenders great psychological and hence physiological health as a lifestyle.

Lastly, as a matter of bibliotherapy, I suggest reading the book The Power of Now by Eckhart Tolle. This is one book that has become a constant companion to me no matter how many other books I am reading because it helps keep my mind clear and calm like nothing I have ever read before. Just saying.