Hi,
This is quite a common situation. If you are to keep the house unless your ex is happy to remain named on the mortgage, you'll hav to ask your mortgage lender if they will allow you to take on the whole mortgage on your own. Whilst this is unlikely as you've recently become self employed you may have to switch to a lender who will allow you to self certify your income (eg; provide no proof).
If you could let me know the value of your property, your current lender and mortgage amount along with your annual income now your self employed I should be able to give you an idea of if you're likely to be able to keep the house, For more in depth advice contact a local mortgage broker from yellow pages - but before making an appointment ask them how much their fee is, don't pay more than �995 at MOST.
Warm Regards,
Dan