People are not contagious for the rest of their lives. This is why a lockdown can work. After time, the virus dies within your body (or you die) and if during the period before that happens you don't come in contact with people, then you've limited the spread. The issue we have now is that we have so many people in all parts of society that are carriers, that even a pretty aggressive lockdown probably won't stop it. The other thing that locking down does is allow the health care system to deal with cases at a manageable rate.
One thing we need to rethink as we go forward is how fragile our society and economic systems are. We've undermined our ability to deal with a nation wide crisis to the point where we can barely sustain even a few weeks of economic inactivity. This means we need a major overhaul. The 41 wealthiest Canadians have enough wealth to have paid for the entire CERB program and then some. We have trillions of dollars sitting idle in personal wealth and corporate treasuries, contributing zero to the economy and zero to the national crisis at hand. Working class people are barely making it, or not making it, and governments have to go into massive debt to keep the nation barely afloat. Meanwhile, Canadian billionaires added $37B (and rising) to their personal wealth in the last eight months. "Oh, but they earned their billions, so leave them alone." No, they didn't. We ALL did.
Those billions were "earned" by using our labour. By using our roads and telecommunications systems and electrical grids and water and sewer systems. Those billions were earned by educated workers that are healthy thanks to publicly funded education and health care. We all did it, we all played a role, and only a few of us shared in the massive amounts of GDP generated in the last 40 years. This hoarding has to stop.