How to stop being toxic, perfectionist, and finally become secure?

Off to a good start, you are very self-aware. You know your strengths, faults, what you want/don't. Now, to change. I know people just like you. One in her 30's the other in her 50's and they are both miserable. Both talented, beautiful women who have terrible self-esteem, and difficulty in their marriages. I suggest you read the most helpful little book called- "Being Perfect" by Anna Quindlen. It will help. Its great that you recognize your need to change at such a young age. Perfectionism as the author puts it in her book is like carrying around a backpack of rocks everyday. Its exhausting.