Note that I am not licensed to practice in your state. This is not intended as legal advice. Please check with an attorney in your state.
There are no laws regulating this issue. However, if you're going through a divorce, your husband could bring this up to the judge and the judge might require you to put them in separate bedrooms. If the judge orders it, then you have to comply.
The applicable factors are evaluated on a case by case basis and depends on the facts particular to your family. If there is a child custody evaluator assigned to your case and your husband has a bedroom for each of them, the evaluator is likely to suggest that separate rooms is more appropriate but it doesn't mean that you can't have custody of the children. In fact, it may be an indication that child support needs to be increased. Feel free to contact me for a free consultation, as my office is in Brandon, Florida.