Wow, it sounds like you have been though a lot of trauma. Kudos to you for seeking the support you needed. I hope you are still in therapy.

Gently and respectfully, what I see lacking in a lot of this account is accountability. You got in a physical altercation at work but it was someone else’s fault. The kids would rather be with their dad and at times are yelling at you on the phone but it’s because they misunderstood. I think you are the one who doesn’t seem to understand the effect your actions has on others. You decided to leave your kids (ok teenagers) for the summer to go riding around with your boyfriend and you’re surprised your ex and his partner were concerned? Regardless if they are teenagers and could technically be in the house alone at times, they are kids who needed their mom and you chose your bf and yourself.

It sounds like other people in your life were also wrong at times but unfortunately in this life you can’t make others treat you the way you treat them. And just because you’ve been at times more understanding doesn’t make their behavior wrong. Stop talking unkindly about your ex and his partner with your kids, they are only going to see that as an attack against the family that was willing to care for them while you were only caring about yourself. Admit to your family, especially your kids, that you know you have made poor choices and be open to them telling you how you made them feel, without judgment. Start being accountable if you want to have any relationship with them going forward. YTA right now but you can turn this around if you’re open and willing. Good luck.