Yeah - saying in the heat of the moment that she should leave is not productive. Cooling off, and sitting her down at a quiet time and saying "This just isn't working for either of us. I think we should live separately. Here's my idea of how that could work with childcare."
All that being said - I probably wouldn't be thrilled about a recently/still sick child coming to a house with a toddler in this time of rampant RSV hospitalizations. ON the other hand, she's a complete hypocrite if she's also taking the toddler to playgroups, as those are pretty germy too.
Also - are you prepared for the child support you would be paying? Speak to a lawyer ASAP and get your ducks in a row. Even better if you can afford to help her get into a new place. (Like first and last months rent?). It is best for your child if she can be financially stable.
