I'm in the same place as you. I've been trying to break into web development for over a decade. The only thing that worked was to accidentally walk through the wrong door and have a chat with people who, it turns out, were looking for a web developer. After finishing the project and coming away with a good reference, I still don't have enough experience to get into the few entry-level web development positions that exist, let alone the more common senior positions. There are too few openings and too many competitors.

Putting myself in the position of a recruiter, I would expect any web developer to know the names of the five major browsers, how to use the w3c validator and why, when to use different image formats and how to optimize them, some CSS, how CGI works, enough jquery to select an element, and a server-side scripting language, and to have once sniffed an HTTP connection to see what was happening. The better class of web developers at the entry level might know why to use SCP instead of FTP, common web security concerns, how to build a page that uses Javascript but does not require it, shell scripting, system administration, web server administration, what a SQL join does, how HTTPS works, how DNS works, how TCP/IP works, and a development framework or two.