It depends, as all things in law. Settlements have multiple components, including pain and suffering and lost wages. The lost wages portion is subject to equitable distribution, the remainder is not. But, the whole lost wages portion may not be subject to distribution, only the portion for lost wages earned during the marriage.
Your situation needs to be flushed out more and I suggest you consult with an attorney to review your case in detail.
The answer to your question requires more details from you that you have provided. Are you in the process of divorce? It depends on what the accident settlement covers. Lost wages can be divided in a divorce if you would have used those wages for support or maintenance of the household or family.
If you were together at the time and she cared for you and was deprived of your affection and assistance because of the accident, she may have a claim for that under your accident case, but it is not usually 50%. Pain and suffering payments for your pain and suffering are not normally given to her. If you are paying support and you are in arrears, that would be taken out of your settlement before it was given to you. You need to talk to an attorney about your specific case.