Big hugs to you Sadshan. I can only recommend you remembering that he wasn't making you happy and you felt distant. Frankly, if a person isn't making you happy, it is time to end the relationship. I reckon he's done you a favour.
Perhaps it's time to figure out why you are so distraught about losing a relationship which wasn't meeting your needs. Perhaps you're lonely and he was your only option? Is your self esteem too low to expect a healthy relationship? Get yourself into some counselling - it will help you through this hard time and hopefully make you stronger for the next relationship you have.
Never regret anything that has happened in your life. It cannot be changed, forgotten or undone. So, take it as a lesson learned and move on.