There are not statutory guidelines on Maintenance (Alimony) insofar as they compare to Child Support. So there's no way to answer that question without a review of your case file, and even then, it's dependent on 3 factors: 1) Facts of your case, 2) Mood of the judge, and 3) The competency of your attorney.
I am not a family law attorney in your state, so I cannot address how much spousal support you would receive. However, if you are asking whether your social security disability would be lower b/c you are receiving spousal support, I can answer the question from the following viewpoint:
1. Social Security Disability (also called SSDI, Title II, SSD) would not be reduced b/c you are receiving spousal support.
2. SSI (also called Supplemental Security Income, Title XVI) is a needs based program. Your monthly SSI check would be reduced by the amount of spousal support you receive. The amount of your monthly SSI check may vary from state to state. However, if your spousal support is higher than your monthly SSI check amount, then you would receive no SSI.