After you've had that much negativity with someone, you are always going to hold some sort of resentment for that person. This resentment builds and builds, until it becomes full blown disdain. Every little argument or joke taken too far is going to lead back to some previous issue you guys had in the past and it will never go away. You could see a therapist, you could both have some fantastic epiphany, you could tell yourselves that it's only until the kids grow up, whatever. Bottom line is you'll both be unhappy, you'll both hate each other and you'll end up playing that on-again off-again game until the end of time. You have to understand that once you reach a certain point of intimacy with someone, things dig a little deeper. You become a lot more vulnerable to each other, and a little bit of spite goes a long way.
On the topic of whether or not to end it now, I think you already knew the answer to that. The relationship is beyond 'unhealthy' and should be given a last meal and put up for the firing squad, so to speak. Make a clean break and let time relieve some of the animosity between you two before attempting to reestablish communication, which IMO, would only be fore the sake of your kids. Your kids will definitely pick up on the aggression between you, which is no better than staying together from their standpoint, which is why it's important to give each other some time to move past the break up before trying to slowly reincorporate boundaries and details that are involved with shared custody. My last bit of advice would be to avoid court at all costs. Many times, it is completely necessary, but if it can be avoided, IMO it's best to do so. If you guys absolutely cannot come to an agreement on any particular terms alone, that is when the court system comes in. Keep in mind, coming up with a solid game plan for custody, financial issues and disbursement of possessions will be a lot easier to do after that cooling off period (No, not 10 days :P) but of course, a lot of the time one or both people involved is going to be unreasonable and unwilling to compromise.. which is when it needs to enter court.
Disclaimer: I'm not female nor have I ever been a female.
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