A message
Talking badly about your ex-p to your children is wrong and that includes talking about money because you are NOT objective at all about it. You are not just "telling the children the truth" you are actually telling them your truth and if your truth is that you hate your ex-p for various reasons and that in your mind you are being treated badly what you are actually doing is being toxic and poisonous and alienating your children from their other parent. You are making them feel that they have to align with you and that there are strings attached on your love - ie, that they "take your side". Its as if you are saying "yes I know you love [other parent} and of course I think that is great but I really think you should know x, y and z about them before you proceed any further". In my view you are a CRAP parent for doing this. I never thought you were crap in any other way but right now the way I am feeling I have decided that this fact alone makes you CRAP. I have a child of my own and I swear on her life I will NEVER come between her and her father - of course it would be easy for me to fill her head with any adult issues that I might have and misuse my position of power but that would be WRONG and NOTHING changes the fact that it would be WRONG.
FWIW you don't actually hurt your ex-P any more. He has already had the worst hurt any parent could have, he had it years ago when this first started happening and he first realised that his child (a Daddy's boy through and through) wasn't allowed to love both his parents and had a made a choice that you were the one he needed to please. He went through the range of emotions: hurt, confusion, shock , anger, grief and now a kind of resignation and apathy. For the last 5 years he has stood there and taken it, taken the nasty words the accusations of things done to Mummy that were not even true (unable to argue as that would be calling you a liar and why stoop to your level), he has had the tears and tantrums, had the phone put down, heard the stories of what his son says about him to other people (funnily enough all the "bad" things are related to you and money!!) but he has never flinched, never shed a tear in front of his son, never faltered, never responded in kind. His son always knows that his Dad is there for him and funnily enough his Dad is still the person he tends to call in a REAL crisis despite everything. That is because he is a PROPER parent, proper because his love is not conditional on his child jumping hoops for him. Your actions have been WRONG and MISGUIDED and most of all have been UNFAIR on your son and caused him huge angst & sorrow but I don't hope that your son ever realises in future what you have done to him because I actually care about him and. neither his father or me would ever see anything good in him rejecting you.
All the alienated parent can ever do is hope that one day the child realises that there were never any strings attached to their love but if this never happens then so be it. Your ex-p never really stood a chance with his son it doesn't matter what he actually does as you are always there to ruin it with your poison and your guilt trips. The fact that a child who adored his Daddy now professes to hate him (well that goes up and down depending on how angry you are with your ex-P that week) is actually NOTHING to do with his relationship with his father (and any normal ups and downs between a teen and their parent) but is 100% to do with his relationship with you and his constant need to prove his love for you. You really can't see that can you.
And isn't it funny that your other child just refuses to play ball and still loves his father deeply. No doubt he misses out on a lot of the special "hate [x]" bond that you and your other son have but I personally have such admiration for his strength of character and his innate understanding that he loves both parents equally and doesn't need to makes a choice. Of course he gets upset at hearing his Dad slagged all the time at home and has confided as much (and yes I find it funny that you are so disrespectful to his feelings) but I told him years ago not to worry about it, I said that we are not bothered by it and that it is not his Mummy's fault it was just an adult thing and told him not to let it hurt him & just let it wash over him - that was actually a lie - of course it does bother us. But we put our own feelings aside for his sake - believe it or not this is a common theme in good parenting. Maybe that's something you could have considered doing yourself….??
Getting this out helps me feel better - I can't say these words to anyone in real life and I love my step children very much and just find it all so SAD even after all these years.