After three years your separation would be considered legal, though there is no documentation. You can still draw up a separation agreement through the legal system if you require maintenance. This is done in family court, and you can use a mediator rather than a lawyer - it's cheaper!

ask yourself do I feel that we will get back together. My answere to you is that if you have been separated for three years you need to go ahead and get some papers filed and establish a divorce and move on if you haven't already done that.