I can understand where you are coming from mate, and agree lifting weights will help in many ways.
have you thought about exploring why you have these challenges? I ask as I went through a journey of my own the last few years, and I can tell you the answer is not in a pill or powder (this I am sure you already know)
in in your early 20s I know it might not be easy to have sufficient perspective to address any issues, and easier to mask or numb the effects and just get on with it.
You hopefully have a long life ahead of yourself, being in constant conflict with yourself is not a fun way to live you whole adult life.
You seem well educated, and probably have the ability to rationalise a lot of your challenges, but I do know from experience you can't do it alone.
Again, not wanting to overstep boundaries or preach...... Just want to see a good young fella make good Decisions
best of luck mate!