ebon hedge
"how to show gratitude"
There are two types of gratitude. I appreciate your efforts. I am thankful for you recognizing my efforts. Practice both of these often enough, and it will be the only thing you see, search for, and believe in. This is how you show compassion for your own circumstances. It is also the only way for you to empower your desire for change.
"how to complain"
For the record and with no judgement, I don't appreciate insert behavior. They may profusely apologize. I do not need to forgive you because you did nothing wrong. You're just doing what you think is right. And if your actions don't align with your truth, you're only lying to yourself. And quite frankly, that is unequivocally not my problem.
"how to equalize"
The first rule of debate is to never allow your opponent to determine the conventions and logic of the argument. Once you allow them to set the environment of their approach, you have already lost. Instead, mention mutual interests, mutual disinterests, and lower the emotional guard of conflict. Only then should you state your regards.