Resigning for good (part 1 )

I worked in a call centre here in the Philippines for four years. first job was for an airline company with a lot of drama about breaking guitars and dragging passengers out of airplanes. I manage to get to a position where I was one of the SME but instantly regretted it after knowing that I need to take supervisor calls which totally messed me up emotionally. I started hating my life and contemplated suicide due to depression about my job and adding the fact my girl left me at the time. I was so lost and depressed one day that I manage to talk to someone asking a change for his ticket schedule. as per policy we have an expensive change fee and the guy is asking to waive it. but as a supervisor call I have the choice to waive it or not. being the dick I am I decided not to waive it because the call was like being monitored and I need to adhere to policy. that person on the other line started cursing on me like he knows me personally and almost lost it. almost cried and he notice the tone in my voice changing and started to feelbad for me. he said he was sorry. I tried to suck it in then decided to go fuck it i’ll waive it. then QA gave me a failing score and left me demotivated ever since. I feel like I have failed as a person. I started dropping calls, hanging up on colleagues, being rude and nasty and worst is transferring the problem to a different person if I don’t like it. one day karma came in and a sup call ended my career. there is this couple who saw the price of the ticket online and wants to book it over the phone. we don’t have that price that they are looking for and asked for a sup. I explained that we cant match what they see online since ticket prices blah blah. then they decided to file a lawsuit which the airlines decides to blame on me for not being the customer always right bs. this forced me to resign and ended up my resignation was thrown to the garbage and ended up terminating me so I cant get my benefits. after serving them for 2 years this is the thanks I get ?