First, do your reasonable best. No one expects you to be Superwoman.
Also, don't withhold helpful information from the court. Hiding his poor behaviors will be self-sabotaging. You may feel bad about reporting or disclosing his mental health history and suicidal comments and actions, but for your child's welfare the information needs to be included with what the court considers.
I don't know the countries involved so I can't speculate on how the courts in your country, or his, will work or how fair they are.
How far away is he? Is it practical to make bi-weekly or weekly exchanges? I suspect not. If he's distant he may have to settle for the longer school holidays and extra time in the summers.
Whatever else happens, do your best to stand firm on this boundary: You have physical custody (or are Residential Parent) at least to the extent that your child when older attends schools in your area with you as the official responsible parent. PwBPD are prone to move frequently, you don't want to be hopscotching around the world following your Ex just to have contact with your son and his schools.
In addition to being viewed as the Primary Parent, you want legal issues to be minimized. That means you don't want to go to court for every impasse on major issues such as medical, school or religion. So if you can't get full custody then get the next best status which is Decision Making or Tie Breaker. Effectively that is very close to full custody but allows him to feel involved since it would be a limited form of joint custody.
Ok I won't hold anything back.
No it is not possible to make exchanges (do you mean eg, him getting our son for a weekend? If so that's the problem, I don't think out son will be safe with him. His dad is easily angered and self harms so I'm nowhere near ok with him getting him alone. I'm all for visits though, as often as he likes, supervised visits would be best especially if he's angry about the situation
