Hello Sisabel,
I read your post with a heavy heart. I wish I could sit with you and give you a safe hug or make you a nice cup of tea or coffee. I greatly admire your courage and candor. It is far from easy to look at our deeper selves, to face our flaws, to acknowledge our mistakes. I have been working on this in my own life. Honestly, I believe that what you are describing is very, very human. We aren't perfect. Not a single one of us. We hurt people sometimes. Sometimes we hurt the people we love the most.
I call it needing to hit the pause button...if only I had hit the pause button instead of making that comment or reacting instead of keeping my peace.
What I recommend is that you try, in any way comfortable to you, to find balance. A balance between self-awareness/monitoring and self-acceptance/appreciation. You mention regret. Regret hurts us so very much...if unchecked, it can scar us and stunt our growth. Regret is not part of the balance I mentioned. Regret, in my perception, is an extreme. Extremes usually aren't helpful. Please don't live your life in regret. You made mistakes and you don't want to repeat them. That truly counts for a great deal.
It will be easier to avoid repeating your mistakes if you are loving and patient toward yourself.
I am so sorry that you are struggling. As strange as this may sound, I want you to know that I have seen some surprising beauty stem from struggles. May it happen for you Sisabel. Peace to you.