Advice on being single in 30s and existential crisis

As a female in 30s, How to not compare with everyone around me, who are married with children , with good careers, without mental health issues ? (I feel jealous of everyone and I am ashamed to feel this way). Feeling lonely and inferior, lost and stuck, miserable, filled with self-hatred, overwhelmed by irrational fears, worries and anxiety . Seems like everyone has at least achieved something in life, whereas I am feeling empty, hollow and broken, without anything to look forward to in life. Nobody truly understands how I feel. I have been pondering about life, adulthood and existential crisis. Was retrenched 2 weeks ago, further intensifying these heavy and suffocating emotions. Been struggling with depression and anxiety for 20 years and overwhelmed by inexplicable terribly lousy emotions (sought professional help but wasn’t entirely useful). Mental health resulted in my unstable employment and changing jobs once a year , taking temporary contract jobs, freelance jobs in between.…..Trying to control and get a grip on my thoughts and emotions but breaking down inside, these dark messy, twisted thoughts incessantly gnawing , haunt and consume me like a plague every single day for 20 years. I wish to be liberated and break free from my thoughts, put a stop this once and for all, and my depression and anxiety to be healed completely…..as I am absolutely sick and tired of feeling this way (stuck in a perpetual vicious cycle, swamped with endless overwhelming loop of thoughts) for 20 years. I have been forcing myself to shake off these toxic emotions and to be functional in life….. Pardon this incoherent jumbled up ramblings Reddit post