Will Desalinization Make the Sea Saltier?

According to at least one environmentalist:

Rivers are overdiverted, causing water shortages downstream. Aquifers are being overtapped. Where is the water to come from so as to safeguard the environment. If you say, "the ocean with desalination plants" that is NOT an answer either - not in the long run. Billions and billions of people...that is a lot of water to take from the ocean with the concomittent pile-up of vast salt extracts. What do you do with that? You cannpt add it back to the oceans because at this scale you begin to increase the salinity of the ocean which would devestate the life within it.

What do you think happens to the water you drink? Does it slosh around inside your body? If it doesn't come out, you will explode. Every last ounce of that water will eventually exit and make its way back to the ocean, where it will dilute all that nasty salt.

The same phenomena will occur with water used in irrigation, bathing, or anything else.