My favorite reference book on the topic is: https://www.amazon.com/Practicing-Stoic-Philosophical-Users-...

My knowledge of Stoicism (in the philosophical sense, not behavioral) is based on recently reading The Practicing Stoic, by Ward Farnsworth (https://www.amazon.com/Practicing-Stoic-Philosophical-Users-...). I recommend the book as a good introduction to incorporating Stoicism into one's life, and I think readers would be hard-pressed to see an endorsement of "toxic ideology" in the thoughts of Seneca, Epictetus, Marcus Aurelius, and other Stoic thinkers.