Yes, some leftists can indeed be very neurotic and bullying toward other leftists. The discourse about this reminds us that something gets lost when we choose to blame all our stress and psychological dysfunction on the system.
While it is true that the financial stress, needless toil and pervasive sense of meaninglessness that people experience under capitalism does dramatically deteriorate psychological wellbeing, we all still have a responsibility to try our best to be decent people and come to a reasonable amount of peace within ourselves. People in leftist spaces who use conflict and puritanical moralism to masturbate their drama addictions and distract from their inner misery are not being responsible with their pain.
Part of growing up and becoming a mature adult is accepting that sometimes the problem is in you, and taking seriously your responsibility to fix that problem. If you're experiencing a lot of conflict and drama in your personal life or online, then you're the common denominator in that equation, and it means you could use some inner work. Take a break from social media, begin a disciplined practice which helps you come to inner peace, and find some methodologies which help you heal your inner wounds. It's not okay for you to keep harming and distressing the people around you with your inner condition, no matter how correct your politics happen to be.
The tendency in some leftist circles to externalize all our problems and always make our distress about an abusive system or a politically imperfect comrade creates a kind of learned helplessness where we assume all our suffering is completely beyond our control. In fact it is entirely possible to come to a great degree of inner tranquility and joy even in the midst of this brutal dystopia, as long as you're willing to take responsibility for your inner wellbeing and do the work necessary to get there.
Healing is very possible. I say this as someone who has needed to do a whole lot of it. If you take this reality seriously and accept your responsibility to do something about it, you can become a much more effective opponent of the empire, and a much more pleasant person to be around.