There is no such thing as being ‘legally separated’ in Ontario (or anywhere in Canada). You do not apply to the court to be separated. Some spouses use the term ‘legally separated’ to refer to the fact that they have a signed separation agreement settling their family law problems with one another. Having a signed separation agreement does not mean that spouses are divorced. You are married until you are granted a divorce by the court, even if you have a separation agreement. Couples can choose to go through the mediation process, come to mutually satisfactory agreements, and document all of their agreements in a Separation Agreement.
For most people, going through the process of separation and divorce is a very emotional time. Even though you may agree to divorce, you might not agree about anything else. Talking to each other, and making mutually beneficial decisions regarding financial division, child & spousal support, and custody can be very difficult. This process often goes more smoothly when a Mediator is present.