My husband and I have been married for 16 years now . He had leave and was living with someone else and have 2 children with her. For the past 2 years we been back tougher. Just want to know can he get a divorce from me without I knowing about it? And what are my rights if such thing are to happen.

In most countries he couldn't do it without you knowing.. however that is most... from your username I think you might be in a Middle eastern country where that might not apply.

What country are you both living in now? Your rights will be determined by where you live.
Edit... I see you have another thread where you say you are in Canada. You will actually have fairly substantial rights.

But you need to be more specific so someone can answer better.