I have been in a wonderful relationship for 13 months. The only downfall was his mother who was very possessive even had a joint bank account together, since his dad left a year ago.Towards the end of this year we discussed moving in together, even looked at some properties.Everything was fine but he wouldn't tell her about the properties but told me that he was going to stop paying the mortgage this month.Then yesterday completely out of the blue he finished the relationship by phone, telling me he needs to be on his own, but still wants to be friends and doesn't want me to hate him, he sobbed and said he couldn't break up face to face because it would make it harder. I am so confused and want him back so much, but I feel he is 27 and feels committed to his mum.What can I do?

Nothing. If he is a mama's boy the only changes that can be made is by him if he wants them.
Move on. Staying with him would only mean more drama. A 27 year old man who will break up with you over the phone while sobbing is IMO, not one you want to be taking emotional risk with.

You know good and well baby boy can't leave his mama, so leave the immature coward alone and count your blessings as it would have never worked with THEM!

Omg this is similar to my story , what all of themk is syaing above is ryte, you will soon know that you don't want to be with a cowrd who can't make decision for himself, its going to be a painfulmexperience , I'm still going through it now but you will appreciate your decision in future.. and dun stay friends because its going to be difficult... stay strong

I think you dodged a bullet.
He doesn't seem mature enough to make his own decision. A boy becomes a man when he makes decisions on his own. Is he doing this because he doesn't want to commit to you or is he doing this because of his mother?
Mothers can be controlling and possessive all they want, but the decision is his if he is able to stand on his own two feet.
Given his decision, whichever of the two mentioned above, he is not worth your time. You don't want a mama's boy because he will always put her first, and if his mother doesn't like you, you bet she will give you a lifetime of trouble. If it is the other option of him not seeing you guys together forever, then it is best to break up as well.
I am so sorry for your loss. Having gone so far and investing so much into the relationship. Trust that it is better now than later when you guys are married and kids are involved.

Guys-this thread's nearly two years old.