You can go and speak with the prosecutor, explain the situation and ask for the prosecutor's assistance with the issue. You may also testify in court at the hearing and explain to the Judge your view on the issues which led up to these charges.
An aggravated assault is a 2nd degree offense and the max bail is normally $100,000. Especially in Essex County this is a high bail for a simple DV. There has to be other things going on like you got badly hurt, or there was a gun, or he has a long record ,or he is leader of a gang and they have been after him for lots of stuff, or there was a FRO already and he violated it. There has to be some other enhancement to get to that bail. Also my guess is that it is not just the DV here but a felony charge as well. The State does not have to drop the charges just because you want them to. You need to speak to an attorney, private or PD, as soon as possible. Call if you like.
I'm concerned about what you're describing. If he's being held on Agg Assault charges with a $200K bail, someone thought something very serious occurred. In my experience the most "real" DV victims are also the quickest to say the charges should be dropped (by contrast, the "harassment" / "name calling" ones seem to never quit....).
You've got to keep in mind the domestic violence is a cycle. Read this: http://www.heart-2-heart.ca/men/page5.htm . While I certainly don't agree with everything many "experts" say on the topic (and the gender bias is disgusting - all one needs to do is sit in an actual Family Court courtroom to see that roughly 25% - 1/3 of cases have legitimate male victims), they are correct on many aspects - including / especially the "cycle of abuse" stages.
If the DV incident you're describing happened, you'd now be in the "honeymoon" phase. I have no doubt that apologies and assurances it will never happen again are sincere and heartfelt, but if you two don't address the underlying issues and find better conflict resolution skills, you'll be back through the other stages and, if the last incident involved a knife, well, that's scary.
More to your question - you might want to get a consult with a Criminal Law specialist if you can get one without cost. In general terms - you don't want to say "I lied"; you would be exposing yourself to potentially serious consequences. That's why the other attorneys who have answered have used the phrase "don't intend to cooperate." If the State won't drop it, you'd do what's called "5 / 5 and out" - you'd both take the fifth amendment and the judge will drop the case. More likely, "real world" is that the prosecutor will put the charges "on hold" for 3 or 6 months and then dismiss it IF there are no further incidents.
Just be sure that's what you want to do - if the incident you're describing occurred, you two MUST go to counseling or its a recipe for future disaster.