I'm currently receiving ssdi can I collect on my exhusband s.s when he retires and will it effect my ssdi benefits
You must be at least age 62 and unmarried to potentially be eligible for divorced spousal benefits, and your ex-spouse must also either be at least age 62 or drawing his benefits in order for you to potentially qualify (https://www.ssa.gov/OP_Home/handbook/handbook.03/handbook-0311.html). If you do qualify for divorced spousal benefits it would not affect your disability benefits (SSDI), but you can only get divorced spousal benefits in addition to your SSDI if 50% of your ex-husband's full retirement age rate (PIA) is more than your SSDI rate. And, if you start drawing divorced spousal benefits prior to your full retirement age (FRA) your divorced spousal rate will be reduced for age.
For example, say Mary is age 62 and receives an SSDI rate of $800. Mary's ex-spouse is over age 62 and his PIA is $2000. Mary's unreduced divorced spousal benefit amount would be calculated by subtracting her SSDI rate, which is the same as her PIA, from 50% of her ex-spouse's PIA. In this case that would be $200 (i.e. $2000/2 - $800). However, if Mary starts drawing her divorced spousal benefit right at age 62 her rate would be reduced to $137. That reduced excess divorced spousal benefit would then be paid in addition to Mary's SSDI, giving her a total benefit rate of $937 (i.e. $800 + $137).