It takes work and time, but that's how you get a network.
I've interviewed dozens of people over the years and the easiest way to be disqualified is to come across as being difficult to work with.
I understand your position, and your frustration, but I'm sure you could have found a more pleasant way to phrase what you said above.
Have all of your jobs been contract-based? That really sucks, I cannot imagine having to worry about contracts not being renewed. Fixed-term employment contracts almost don't exist in our industry where I am. I'm sorry you have such a hard time finding companies looking for stable long-term employees. Random tip that might be helpful with your next job hunt if you're not doing it already: never answer the question "how much were you making at your previous employer?". Tell them how much you want to make NOW (+ $5-10k/yr padding) and negotiate down from there. You're instantly setting an artificial cap in their minds once you admit to how little you were willing to settle for previously.
As for climbing the salary ladder if it doesn't happen naturally over time, I'm not entirely sure. There is one truth I can extract from your comment, based on discussions with coworkers over the past decade: frontend devs have a tougher go at things, and me being a primarily backend dev looking at the work frontend devs do, I don't understand why that is. Backend devs seem to be appreciated more, and I agree that it's nonsense.
One loosely composed answer is that backend devs form a circle jerk of touting our profession and work as important, and we demand proper compensation to match. The personality traits of the frontend devs I've met are less aggressive on the whole. As in, on a personal and professional level, frontend devs are much nicer people. Perhaps the industry translates this to mean "pushover", and is taking advantage?
A better analysis would be that the industry hasn't caught up to what it means to be a frontend dev today. 15-20 years ago, learning HTML, CSS, and early JavaScript was not a difficult task. Every backend dev was also doing everything for the frontend, so a "frontend-only developer" would have been seen as someone worth less than a "full-stack developer".
As of 7-10 years ago, this has all changed. There are very few devs who are truly "full-stack" anymore, to the point where the ones who claim to be are mostly liars, carrying their outdated knowledge of HTML and CSS from 1995 as if they are marketable skills. Today's seasoned backend devs are rarely well-versed in everything CSS3+ and HTML5, let alone ES6, Canvas, WebGL, and all the tooling (css preprocessors, grunt, gulp, webpack, frameworks with build processes, etc.).
In the distant past, frontend work was a nice-to-have addon for backend devs to have in their toolkit. Today, they're completely separate disciplines, and the pay should reflect that fact with equal pay for both roles. An expert frontend dev today is absolutely worth the same as a backend dev. The industry needs to realize this truth and fix the salary gap. A developer is a developer, is a developer.
I have worked in multiple small (~20 employee) companies, most for over a year and a half. I have 8 years of total experience as a web developer. During that time I have not made any reliable long term contacts that can refer me to any relevant work.
Second, ALL of my past jobs have paid 40-50% of the local market rate. Each one I have earned more money, but it's still well below average for the large Midwest city that I'm in.
Every few months I return to Facebook, post to my feed so friends can see, announcing that I'm still looking for work and if anyone knows someone looking for a web developer. Usually I get no replies.
So you see, even with my years of experience, I have been unable to rely on a network for jobs, and recruiters have also been ineffective.
Now, with this new information I have given you, I am more curious to see what you would suggest, as something more tailor-made to my career experience.