I think you need to see an attorney and get some idea of what you would likely be able to get in child and spousal support. Even if you don't file, it will help you to know what is reasonable (for instance, if he's already giving you way more than he would have to pay in a divorce, you may not want to rock the boat and may want to delay divorce as long as possible. On the other hand, if he's giving you way LESS that you would likely win in a divorce, you may want to get that ball rolling sooner rather than later.
