Stress around boyfriend's teenage son

I am feeling stressed by my boyfriend's teenage son who lives with us and the entire situation between my boyfriend and his son. I understand that the definition of an 18 year old boy runs along the lines of me me me, "I know I know" (everything), etc., but the kid is so disrespectful and lazy in mind and action that it bothers me. My boyfriend's ex is a yeller and high anxiety controller type; she will literally call 6 times in a row to try to manipulate him into a frenzy about anything anytime. She took him to the cleaners in the divorce 8 years ago (house, support, etc) and never has enough. Unfortunately her pronouncements of “father abandoning child” were so incessant; my boyfriend holds terrible guilt about the divorce. She drummed this into her child, my boyfriend’s family, etc., etc and poisoned everyone around the boy, manipulating her hurt into using her son as a pawn. My boyfriend has always been involved in his son’s life, and there was no abandonment, but he took her warped anger inside himself as guilt.

He has learned that he has the choice not to answer the phone and is very good about that; and simply will not deal with her at all, which I can't really blame him for. But it seems that the complete lack of communication between the two creates a situation wherein the son is in no man’s land and probably feels that he has to figure where to go at this point in his life alone. This is a time where he probably wants direction, but is resentful that it is not forthcoming in a gentle guiding way from either parent. Anyway, the kid barely graduated high school, and his dad let him take a month off before getting a job, as well as not going to community college until January, and it wasn't until August when he finally got a "job" (maybe 20 hours a week) only to quit last week because he wasn't getting the raise he was supposed to get. What the hell are these kids thinking anyway?

The son always flies off the handle when his father tries to raise the issue of a job - He thinks he should be making $15/hour and has a sense of entitlement to beat the band. My boyfriend always backs down to these tantrums. The son falls asleep on the couch every night with the TV on, wakes up at 2pm only to "hang out" with various friends and appears to me, God help me, as simply a user of everyone around him. He hasn't gotten his driver’s license (Why do I need it) and always jumps with an argument when his father tries to talk to him about anything be it how are you doing, do you want to check out college, etc. To me the son’s behavior is civil at best.

I find myself unable to be around the house when he is here because I am so angry and resentful of him and his father's enablement of this horrible behavior. I think I just needed to get this out, and appreciate this forum and any words of wisdom from anyone.

[RockRose]

From  my perspective,  this isn't really horrible behavior.  Lordy I've seen horrible behavior in teenage boys,  and this is like, lukewarm behavior.    I'm really surprised at what I've seen in some of the boys I've known since kindergarten - and I think they'll either end up dead on the streets or in the penitentiary.  

What this boy is,  it seems,  is not motivated.  He's going to community college in January?  If he sticks with that,  that's okay.  So many boys graduate from high school and do a little floundering because they really don't know what they want to do.  It doesn't sound like he's found his passion.   That's such a huge thing - when a young man discovers what is really thrilling to him - and what work he wants to do for his life career.  Before he knows that he's kind of just adrift.  

What  can be done to help him find what he really want to do with his life?

Best wishes.