Can you live comfortably on the salary of a theoretical physicist? Also, after getting a PhD in theoretical physics, what jobs are there?

Hello. I'm currently an undergrad physics student, and I'm really loving physics so far. I'm double majoring in Physics and Mechanical Engineering just to keep my options open, but if I had to choose what I like, without a doubt I would choose physics.

So is there any way to live comfortably while being a theoretical physicist? I'm 100% certain that given the chance, I would go for a PhD, but my main concern is being able to make a living. I don't necessarily care about being rich, and I know that I won't be if I choose to become a physicist.

My second concern is the types of jobs that will be available to me as a theoretical physicist. Will I be able to continue researching if I want to or will I be forced to go into industry rather than research if I want to make a decent living? Again, I don't care about being rich, just that I won't have to be living paycheck to paycheck my whole life.

Also, what salaries do theoretical physicists usually make, and what jobs do those salaries correspond to? Thanks.