St. lawrence seaway has been called canada's highway to the sea because

As it connects the ocean by a passage of locks and is non continuous  channel.

Explanation:

As about 45$ of trade activities place through this water way. and is able to generate about 238,000 jobs on Canada and the U.S, and is opened since 1959, and flows from the Lake Ontario to the Atlantic ocean. It generally advertised as the highway of water and is under Canada's jurisdiction. Has a 15 locking system and was the first proposal mad for the hydropower projects in the '80s.

Because of the volume of goods that travel to its length

Bwould be my guess |-/ 

Although this may be the opposite of what you think i will say it anyway. you were brought into this world for a reason and you still have soo much ahead of you. not everybody has an opportunity of living a great life, but it doesn’t give you a reason to end everything. somebody in the world loves you, and imagine what you would do to them if you left forever.