I've been paying alimony since 9/07. As part of the divorce settlement agreement I also pay for COBRA insurance, which will expire in 8/10. I recently discovered that I can claim the COBRA payments as part of the alimony as long as it was stated as such in the settlement agreement. I did not claim this deduction last year, but I do plan to claim it this year. Can I recover this deduction from last year and add it to this years taxes?