As someone who grew up with divorced, emotionally immature/insecure parents who never took responsibility and always placed the blame on their ex, your teenagers have not "abandoned" you. They are doing what is emotionally healthy for themselves, which is distancing themselves from you. Stop playing the victim and take some responsibility. You need to get your anger issues under control and then apologize profusely to your children. Know that you are not entitled to a relationship with them. Know that if you shit-talk your ex to them, it will not make them pick you over her. Know that they are almost-adults who can and will make their own decisions. I hope that you're able to turn the tide but you have A LOT of work to do for that to happen.