There are many experts out there vying for attention. If they don't have deep knowledge; all they are offering is a quick fix. They are just hustlers. To me this is just 'desperate for a buck web marketing.'
Don't go there.
To set yourself apart you do need deep knowledge and experience in your field. If it is relationships, then focus on relationships. However, I would hope that you have qualifications and experience in that field.
I have worked with a social worker who had extended her studies into relationship counselling. She was in her early 60's and had spent many years counselling families and couples.
I worked with her on her target market and how best to reach out to them. It wasn't hard to put together a website of her writings specifically answering the problems couples faced, both gay and heterosexual. She knew stuff, could write clearly and knew how to help people.
I even used her for relationship counselling myself when I recently got married and wanted to work on a few things with my partner.
I also worked with an alternative health practitioner who wanted to target women with fertility treatments. I knew he had no deep knowledge or any experience in that field. I couldn't help him. Nobody was going to believe him, unless desperate.
I have since worked with a Gynaecologist with deep knowledge, experience and know-how of in-vitro fertility treatments. The difference between these two was huge, one a wanna-be the other an expert. Guess who gets all the fertility work in their target areas?
To set yourself apart from the competition is to get out there and do the work, write about it and keep at it. This takes time, often many years.
If you have that expertise, then what you are asking for is how to reach your target audience. That is down to marketing and choosing channels to reach them. I think a WordPress website is the way to go for creating the articles that people area searching for to solve their problems. They are looking for answers.
You may be able to solve their problem.
Do read widely in your topic, practice, and check out some Cal Newport's writings or videos on deep work.
I think it is better to take small steps and build up a long term proposition in something you are really good at helping people with.