The late-filing penalties can make this a costly mistake. As you see, the standard late-filing penalty is 5% of the balance owing and an additional 1% of the balance owing for each full month that your return is late, to a maximum of 12 months - but as you haven't filed for several years, the penalty could even be higher.
You may be able to decrease the penalties by using the Canada Revenue Agency's Voluntary Disclosure Program; this program "allows taxpayers to come forward and correct inaccurate or incomplete information or to disclose information they have not reported during previous dealings with the CRA, without penalty or prosecution" (CRA).
Another thing you can do is to hire a tax lawyer to mediate with the Canada Revenue Agency if you can afford it.
You definitely need to file your taxes on time this year, though, and get your past tax situation sorted out because the longer you put it off, the worse it will get.
Related: Canadian Income Tax and Your Small Business - All the information you need to know about preparing and filing your Canadian income tax return.