Has your STBXH been diagnosed with anything? Everything you describe about him sounds exactly like my XH who has a dual diagnosis of pyschologically dependent on alcohol and bipolar II disorder.
The temper, the manipulation, the threats - don't let him break you down!! Stay strong for you and your LO!! You're doing the right thing!

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Re: ::JCGreen::
After being picked up for his 4th OWI, driving without a license, on the wrong side of the highway, and almost hitting a police car head on, he was released from jail, came home and threatened to commit suicide. I called 911 and they took him away to the psch ward at the hospital for 3 days. After that he started working with a psychiatrist who diagnosed him. He took meds for a couple of weeks and then elected to stop them (so he could drink), so even though he's been diagnosed, he will deny he has any sort of problem, won't get treatment (that only lasted a few months), and won't take meds. It's incredibly stressful to deal with and I know exactly what you're going through. ::Hugs::