I spent five years in enterprise sales and felt almost exactly this way. I was excellent at it - six figures, President's Club every year, the whole thing. And I was absolutely convinced I was part of something soulless.
Then I left for nonprofit work. The pay cut was rough, but I was going to finally do something meaningful, right? Here's what I learned: nonprofit marketing has all the same mechanics. We used the same persuasion tactics. The only difference was that we were convincing people to donate to our cause instead of buying software. Spoiler alert: I wasn't suddenly a better person. I just had fewer resources and lower impact.
What actually changed my life wasn't the job switch. It was separating my identity from my work. I'm not a marketer who happens to exist. I'm a person who does marketing to pay for the things I actually care about - my family, some hobbies, the ability to take time off.
The guilt you're feeling might not be telling you to quit. It might just be telling you that you've tied too much of your self-worth to what you do for forty hours a week. Try this: get weirdly good at something else. Volunteer. Learn an instrument. Start a project that has nothing to do with your resume. The job gets smaller when you stop making it your identity.