Your relationship was obviously failing. It went sour and there was nothing you could do about it. You're not the only one who has had a relationship not work out and you won't be the last. Relationships fail A LOT.
I will do my best to reply with an educated, humble and honest answer. Ultimately, it is up to you whether you want to listen to my advice or ignore it completely. Sometimes, my advice may be wrong; occasionally, it will be right. Regardless, I want to do my best to give people answers they are seeking.