Hello Ariel,
I’m so sorry to hear about what you’re going through, it sounds like a difficult position to be in, and a tough decision to make.
It’s not okay for your partner to make threats about, or towards, your son. This is intimidating and controlling behaviour. Your partner should not be judging, or trying to control your parenting, or your relationship with your children in any way.
A supportive partner should ask you how they can help and support you, if they can see that you are struggling in any aspect of your life. Not causing you more stress, or triggering fears from the past by threatening violence against someone you care about.
Do keep posting and let us know how you’re doing.
Lisa