I don't think that you can get tax relief on interest not paid.Possibly asking for an interest only period but this would most likely be refused. Another consideration would be that I assume that TRS for the missing payment would be lost.
You should do what is advised above and engage with your lender (possibly under MARP) to come to some mutually agreeable arrangement to deal with your debt.
http://www.keepingyourhome.ie/