On the "love you" question, I agree that one shouldn't use the exact phrase "why haven't you said you love me yet?". It comes across as an attack.
However, after one year, it is perfectly OK to ask how he feels about you. If he again says "you're the best thing which has happened to me", it's OK to follow up with "do you love me?". If he can't give an ILY when you ask directly, then I agree that you need to reconsider staying with him. If he doesn't love you after a year, it's unlikely that he ever will.
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.