My rent alone is 52.5% of my income (bills excluded) and my partner is well-off. What are huge stressors to me are nothing to them. Advice?

I graduated with my master’s degree a year ago, and am one year into my first post-grad job. I get paid $30K per year and try to do side-jobs when possible. I’ve asked for a raise but I’m not holding out, and am applying to other jobs. My partner of 3 years makes enough from investments that they don’t need to work, so money isn’t really an issue. However, my partner is used to luxury living and I simply can not afford that. We’ve been living together for 2 years and rent is more than half of my income. I’m constantly stressed about money but it’s hard to live frugally when your partner doesn’t like frugal. What can I do?

Edit: Thank you all for the advice. I’ll have a sit-down talk tonight, I’ve just been ashamed to admit how hard this is for me and trying to keep my head above water.

Should rent be 30% of my pre-tax or post-tax income?

Regarding my education vs pay: I’m trying to find a better paying job. I know I’m being underpaid but the job market was so competitive after graduation that I had to take what I could get.