OK you've "been on a boat once" and your biggest concern is seasickness? Not your ability to sail or maintain the boat? This is not a well thought out plan.
It sounds like you're just looking for the easiest solution to a difficult situation. Doing something because it seems to be the easiest solution is usually not the right solution.
You need to be passionate about wanting a cruising lifestyle. You can do it, but you will have to work hard at it BEFORE you start looking for a boat. Sailing can put your life and your family's life at risk if you don't know what you are doing.