13 Answers

I would stay out of it.  Your son needs to live through this experience however things may turn out or painful,  it may be.  If you say anything about his ex-girlfriend he may look upon your actions as nosing into his affairs.

HE is 30 years old. I think he need to handle his own affairs.

I do not see why you need to tell him unless he thinks she's going to come back to him. If not, leave it alone. He needs to go through the steps of grief that all people do when a relationship fails. Telling him this would only hurt him and make him angry. I just don't see the point. 

If he's not over her , he has probably already seen the picture. Un less she blocked him

Apparently she found someone she thinks is better for her thats what the dating thing is all about.

Tell him and suggest he move on...

No!!!!!! I have a client that is involved with her son and his ex and it is just a complete mess. You raised your son to be what you felt would keep him strong, safe and independent as a man. By interfering here you are taking away from everything you spent his childhood trying to teach him to be. This is his relationship, his time to hurt and his time to grow from it. If you continue to step in you are not giving him your trust that he can get through this. I know it's hard for you to see him hurting but just realize that without this, he will not continue to grow as a man. He will willow under your care. He will get over her all on his own simply because he has a dad that has loved and raised him to be everything you hoped him to be. This too shall pass.

Tough question.  Being a mom, having a child (no matter how old) hurting and brokenhearted is the last thing we want for him.  If there is any way to protect them, sometimes too often we will go to any lenth to do so. 
In this case, my initial thought was "ABSOLUTELY NOT!"  At 30 years of age,  and 4 years into the relationship, it might have been time to S - - t or get off the pot.  I lived with a guy for almost 9 years.  About the last year or so, I was very unhappy we were not moving to "the next level", which would have been marriage.  I wonder about the commitment to have them still just dating after four years.
On the other hand, when someone you care deeply for and have spent alot of time with begins seeing someone else and becomes involved with the new person, it is almost paralyzing to be hit in the face with it, and I speak from experience.  HOW someone could have told me and made it less painful, I sincerely do not know.  It just hurt so badly, in a number of ways. 
As clu said, unless the woman has blocked him from her FB, he already knows.  For you to tell him.....it's just not OK.

No, you should not tell him. Mind your own business.

The answer is no

I feel i would tell him,just in case he thinks there may be a chance of them getting back together.Once he realizes she has moved on,he can do the same.

What would be the benefit to him of knowing? This is the question I would ask myself before doing anything.

Mind your own business. Should they reunite you will be the bad guy.

I don't think I would. He'll find out on his own soon enough, one way or another. Sometimes, to hear it from a parent, is not an ideal situation. People need to feel they have the ability to work through things, without feeling like everyone knows their business.