0 income spouse student loans in federal collection. How does it affect married partner

My wife is a stay at home mom who takes care of our 4 children she has a huge amount of student loan debt from her double bachelors and masters degree. Her student loans are now in federal collection. Can they garnish our tax return if we file married filling jointly, when she has no income and I am the sole provider for our family? Would it be better to file married separately or head of household if our return is potentially jeopardized because of her student loans in federal collection status?