In many countries legal separation is a legal step married couples can take towards divorce. In many cases the couple is only considered legally separated if a court has recognized their separation. However, even with a legal separation, couples may choose to remain married.
Some countries and some states within the United States require a period of legal separation before a a couple can divorce. Laws vary from state to state and from country to country.
She needs to talk to a lawyer.
I think your friend really should have consulted an attorney before she signed anything. I hope it is not to later for her but she did sign the agreement. She really needs to contact someone with legal expertise.