So SEO work is what you mean by digital marketing? I assumed that SEO was in the realm of internet marketing and digital marketing was more of making graphics and digital images to promote companies and what not.

If you have such an extensive background in SEO, that gives you options.

You could perhaps do what these companies are hiring you to do for yourself. You could start a monetized blog or website of some sort and promote it with your knowledge and reap the rewards yourself.

If you're interested, here is a couple of sources for you to read further on this:

https://www.blackhatworld.com/

Warrior Forum - The #1 Digital Marketing Forum & Marketplace

Alternatively, you could look into something called CPA marketing. If you don't know what it is, CPA marketing is where you promote people's products or websites for a commission. If you are already solid with SEO, you could potentially turn a pretty penny off CPA marketing.

Here's a source for you:

20 Best CPA Affiliate Networks (Top CPA Network 2017)

You could do this kind of stuff alongside your job search in the mean time as a way to make extra money to help out. Alternatively, you could eventually transition into marketing your own stuff or CPA marketing (or whatever method works for you the best) full time and not deal with the drama and B.S that comes with working a regular job.

And no, these aren't my affiliate links so I'm not earning anything from posting these. I am just trying to help a member in need here