I was reading a brief description about the reception that Amsterdam gave her in 1638, but the author made it very clear that political circles were not fond of her. First of all: what does the expression mean? Mother of ruin? I can't find a definitive answer. Second question: why did she have such a reputation even in Amsterdam?
This term is an Italian pun on "queen mother" (reina madre). It's not strictly grammatical but the pun is obvious. Rouina is an archaic term for ruin used in several romance languages. She was the mother of then-reigning Louis XIII of France but was out of favor with the king and living outside France, so her political career was a "ruin".