**Tax Year 2018 or earlier** I use a portion of my spousal support to pay the mortgage, taxes and insurance on the house I live in which is 100% in my ex's name. Is this portion non-taxable?

Tax law says that payments to keep up the payors property are not alimony. Since I pay a significant portion of my spousal support to pay my ex's mortgage (even though I live there) is this portion considered alimony? Is it taxable? If not, can I deducted those payments from my total alimony received?