Marketers have a lot to worry about on a daily basis. Your job should not be one of those things.
Any time spent thinking about or worrying about job security is time that could have been spent trying to grow your company. It costs the company money. It costs you money. And we should do everything we can to eliminate job security from the list of things we need to worry about.
How? Become indispensable.
Become the person at your company who knows everything. Become the person at your company who knows how to do one particular thing no one else can do, or wants to do. Become the person at your company who knows the latest news in your industry. Start a newsletter. Send out a weekly update. Bring in snacks.
Do whatever it takes to stand out from the crowd. Make your boss and your team notice you. Make yourself impossible to replace.
You do this by being good at your job. But sometimes it takes more than that. Go above and beyond to become indispensable.
Then the rest of your work will be that much easier.