This often happens to a lot of people, me included. I tend to start things that I cannot finish. Sometimes, I get so overwhelmed by things that I get illogical. It's true what they say not to make decisions when you are happy cause you tend to make stupid decisions that you will later regret.
It's so sad to think that during this process, we hurt other people. Seeing others get hurt because of you is not easy, but if that's how it should be then there's nothing we can do about it. Life is like that, sometime you get hurt, sometimes you hurt other people. It's a cycle. That's life. we can try to avoid it, but it will run after you no matter what. I have one philosophy about choices and decisions and that is, no matter what the outcome, no regrets cause you chose it. Stand by it and accept the consequence.