"He told me that I was the love of his life, that he had learned to love when we were together."
Kind words but that, words. Does he offer actions to support this?

"However, he told me that he was tired of our arguments."
This is a red flag in my book, bordering on manipulation and narcissism. He could end the arguments - if he wanted to. He's blaming you for them, basically, saying the problem is yours.

"And that he thought I was trying to limit his contact with his mother. That he was overwhelmed by the fact that he was standing between two important people."
His mother will always come before you.

If you were in a healthy relationship, this wouldn't be happening. We learn these types of things once we have relationships of our own. Some relationships last a lifetime, and others last a season. I highly doubt this will get better and if you stay, you'll just be strung along.