Ex is brainwashing my son, and now accusing me of abuse

[barbyr71]

Anyone out there that can help!
I have been divorced from my ex since 2001, and he has always been a lying manipulative man. Although I disliked his ways, I NEVER denied him visitation or extra time with our 13 year old son. I even stayed in a stat 1300 miles away from my family, so our son could be near his father. Mind you, we ended up in this state, because my ex irrationally moved the family to this state while I was just in a 14 week training session for the military--due to be back in the state we originally are from. My ex has always tried ot sabatoge every career, educational, or social climb I have made during our entire marriage.
When we divorced, I had physical custody of our son. I worked hard to keep us afloat. I had my credit ruined due to my ex purposely not paying anything that had my name attributed--even my eduacational loans. All this done while I was training with the military, so I was unaware of the negative impact my credit was facing.
My ex always ad a high paying, mangerial career that paid beyond $70,000 a year.
When the divorce occured, he began to quit working at the jobs that he was previously being paid high salaries--he now works as a journalist for a free newspaper, and claims to only make 27,000 a year.
I have been working 2 jobs to support my son and I. I make a total of $28,000 a year. Living expenses are extremely high where we live.
This past year, I met and fell in love with my fiancee'. My son, naturally for a preteen boy, was upset. He never wanted for me to be with anyone. We have always been inseparable. I volunteered for many of his activities as coaches, aids, camp leaders, etc.
Bad news: I have not seen my son for almost a year now. My ex, at the opportune time of our son's vulnerability, had convinced him to tell court, social services, and his school guideance counselor that I abuse him mentally, verbally, and innuendo to sexual abuse.
I have been fighting so hard to prove myself innocent. No one wants to listen to the accused, and I have a protective order against me.
To make matters worse, my fiance and I learned we were having a baby. This we welcomed, and are thrilled. Also, my fiance's 11 year old son came to live with us full time. Financially we are drained. I developed high blood pressure during pregnancy, and ultimately our daughter was born premature due to onset of preecalpsia.
My son, has no remorse, and is so vengeful to get me in as much trouble with authorities as possible--I know this is fueled and planted by his father.
His father has often made our son a spy before my engagement--and during when I still had him. He has our son report every detail of our lives.
He convinced our son that I had cheated on him, and that "our family would still be entact, if your mom (now I am not even called mom, but by my first name) left us for another man.." This is far from the truth. I filed divorce from him because he was a control freak that would demand I be secluded from my family & friends.
How can I get the authorities to see the truth?
My ex is amongst the best of liars....he grew up in a family of used car dealers. His profession was in the car sales market, and was always a top salesman....his career was to lie & be believable, if this can give you an idea of how good he is at it.
I am most concerned for our son. He lies all the time now to the therapist, his personal hygiene is terrible, and he is no longer participating in the activities he has been a part of for many years. My family has no contact with him anymore. His friends ask me all the time where he is, but I can not give them an answer as to when or if he will come back.
Please someone, help me find the right path to get my son back!!!!