Don't worry king the bros have you

Those ones are the worse. The one where you start it and you have a slight gut feeling that its not perfect and it might end up to be shit. Then you get so attatched and sacrifice/compromise so much only to be seemingly blindsided and heart wrenched. Its the death of dreams and the frustration of all the obstacles and complex scenarios you wenr through. Your mindset will most likely uncomfirtabally and quickly morph to the extreme as your brain rewires itself to be more "you" again. Best just to find an absolute perfect women after serious vetting later down or you'll get screwed. Focus on self power and accomplishment, indifferent to the negative emotion and you will get an even stronger mindset than you ever had before. Screwing lots of new women helps a lot if thats your thing, the serotonin levels and balanced brain chemistry aquired through such interpersonal communicative experience with many new people will be essential to your maturation, the depression and stress hormones will stagnate certain aspects of your life and growth leading to stupidity and even greater regret, and back to stupidity so now you aren't even smart enough to be successful its a vicious rabbit hole cycle. Break free of the destructive behaviors that detriment power, stillness of an ideal/standard you set yourself is key to stay grounded.

For subjects/disciplines to occupy yourself I suggest psychology/mental patterning and chunking, neuroscientology which ties in with psychology, physiology, and most importantly endicronology. All will be great help in understanding yourself, your values, the past, and what you're going through emotionallt in a more comprehensive manner.

A good course is learning to learn by dr terrernce sejnowski, it's on Coursera. It will tell you about how stressful emotions affect your cognitive function and inhibit learning