Can I file for divorce in Alberta before we have been separated for one year?

This answer covers the law of Alberta.

Yes, you can start a divorce on the one-year separation ground before the year is up, but you cannot ask for the Divorce Judgment until the year has passed. The Divorce Act requires the spouses to have been living apart when the proceeding started and the full year to be complete when the divorce is decided.

You can be separated while still under one roof only if you are in fact living apart, which is a question of fact for the court. A short reconciliation does not restart the clock if you resumed living together for no more than ninety days in total, with reconciliation as the primary purpose.

Adultery and cruelty are alternatives, and neither needs a year of separation first. Cruelty means physical or mental cruelty that makes continued cohabitation intolerable. For adultery, the other spouse must in most cases be willing to sign an affidavit admitting it. Once a judgment is granted, the divorce takes effect on the thirty-first day after it is rendered, unless a court shortens that period in special circumstances if both agree not to appeal, or a pending appeal delays it. Whether these grounds fit your situation depends on the facts, so a lawyer can confirm.