Under the Divorce Act, you do not need to prove that your spouse was at fault in order to get a divorce. If the reason you are asking for a divorce is marriage breakdown, shown by one year of living apart, either of you can request a divorce. It does not matter which one of you decided to leave. In fact, the law gives you the choice of applying to the court together to ask for a divorce.
However, if the reason you are asking for a divorce is marriage breakdown because of adultery or mental or physical cruelty, you will have to have proof of what happened.