My former boyfriend of almost 8 years has an overbearing mother that controls him emotionally in everyway. She puts him down saying that he is an embarrassment to her because he has not finished college, is overweight etc.

He calls her every night asking her questions on how he should live in life and his finances. She disliked me and because of this my ex used to physically abuse me because of the stress.

Their bond is so unhealthy to the point that when he visits her or vice versa he sleeps with her (not sexual). When I went to the supermarket with them once I have even seen them hold hands.

She advised my ex that if we were to get married, she told him that she would not leave him any money in her will for him, and he is her only child.

My ex ended up cheating on me with a girl that his mother approves of, and in less than 2 months they are already engaged, when I was with him for almost 8 years and we got no where near close to that.

His mother is currently going through a divorce and soon she will be living with my ex and his new bride once it is all finalised. He puts his mother as no. 1 and his spouse no. 2. He is 27 years old.

Can you see my ex changing his ways?

He is obviously very emotionally attached to his mother, this is a bond even I could not change over all those years when I was with him, the whole ordeal has effected me mentally and I am now seeking counselling for it.

You should be happy you are out of that. He is weak and not worth your time. Move on. Happiness is free.

I wouldn't say that he is weak, rather, that he seems to be a very dependent person. Whether that is due to nurture or nature I can't say, however, I do agree with atyourservice that you shouldn't allow yourself to feel weighted down by all this.
I can only sympathize with you, that you were treated so badly because the man you were involved with was so attatched to his mother. And, I can only encourage you to try and move on, to submerge yourself completely in your hobbies, or activities.
I don't think you ex will change, I don't think that he will become an independent individual, however, that does not mean that you have to suffer. You need to let go, and begin living your life again.

Carpe diem. Seize the day.

-m

Remember, his mother raised him to be completely dependent on her however, it is and always has been his choice whither or not to allow her to do these things.Not surprised about the divorce these enmeshed relationships are the product of unsatisfying marriages the children become the "covert" spouse. Be glad you are out she will never let him go, he is her love and he likes it! They are sick!