I have been divorced for 4 years, my ex just recently started seeing our children after 3 years and my 15 year old son has decided that life would be better for him with his father. There is very little discipline, much favoritism shown to my son over my daughter and their father flat out tells them they do not have to listen to me. My son is a very troubled teen that I am trying to help and do not think this would be in his best interest. Do I have options

Well first what is the legal custody agreement that you have though the court. Who has legal physical custody ( you? ) and does he have court ordered visitation?

To do anything different from what the court has ordered you will need to go to court ad get it changed.

I am the primary care giver and he has visitation which he did not exercise for almost 3 years. It is a very long story he is very manipulative of the situation and while I have encouraged the renewed visitiation it is coming back to haunt me because as I said in my original email he is using the situation to his advantage. Our daughter is not buying it but our son is being sucked in. He is a very troubled teen and I am afraid a court battle will back fire in all of our faces because I am afraid that he is so far gone that the courts will take him from both of us.

I think the most important thing you can do is get counseling for your son. You will need to participate, and make an effort to get his dad involved after a couple of sessions. Here is why: The dad can make waves if he likes, but he has to prove you unfit to care for your son, or your son has to prove it in order for you to lose custody. It seems clear your son needs guidance from an objective party, so counseling is a great option. Also, if your ex decides to pursue this legally, the court will see your effort to make your son's life better, happier, and healthier. If dad participates too, they will probably leave things alone, at least for a while. If he doesn't, you most likely have nothing to fear. Sometimes knowing a child is seeing a psychologist is enough to sort of coerce the other parent into behaving more appropriately. After all, someone in a position of authority is hearing everything that goes on. Just a thought.

It would depend on what you mean by so far gone.
They could order counseling for him (your son) or family counseling and you could tell the counselor what you see as his problem and how the dad lets him get away with everything.
I really don't see Child protection service taking teens from parents unless it is pretty bad.
What I have seen they say he is your kid you have to deal with it, but then again it DOES depend on how and what he is doing. Like if it is average teen rebellion or if he is beyond that.

By too far gone I mean I seem to no longer be able to handle him. He has been in trouble with the police and also was expelled from school for a year. I am seeking counseling and will participate fully. What I am afraid of is that the court will say I can't handle him so lets give Dad a try. After a 3 year absence and what is going on over there I just can't see how this would be in my son's best interest.

You have custody. For him to go live with his father you have to agree with it or he has to get the custody order changed.

Don't harp on his three yr absence. That may bear on the judge's decision, but probably won't.

Thank you to all have responded to my questions it has been most helpful and I feel like I have a better grasp on the situation. I know not to focus on the absence but rather the behaviour that has escalated since the visitation has resumed.

My one son acted up really bad (violent) and I had to 302 him to the psych ward many times.
One of the reasons he acted so bad was because he was hurting that he did not have his dad in his life. He was taking his anger of his father never wanting to be bothered with him out on everybody else.

Thank you...

I know that desperate times are calling for desperate measures. The problem with my son is his Dad is back in his life and encouraging all the nastiness towards me saying it is my fault I can't handle him... he doesn't have to listen to me etc... it is a mess

Just try not to get drawn into it. I know it is hard to hear those things your son's father says, but at the end of the day, you are the only person who determines what sort of relationship you and your son have. But don't give dad's claims any credence by getting into with your son. Be willing to hear it, accept that dad is saying it, and let it pass through your ears like empty static. Responding to it by arguing your side or getting angry will only make you less credible. Stay strong. It isn't easy, but you can do it.