The road forward is straightforward but very long and bumpy.
The first step is to pass S3. The USMLE has no time limit on exams, so as long as you've passed S1 and S2 you can take S3. There is now a 4 attempt limit -- you mentioned that you had not passed the exam but not whether you had failed it. The attempt limit used to be 6 but is now 4 per step -- if you've failed 4 times already then your medical career is over.
Once you pass S3, then you need a state license. Some states have a limit on the time frame in which you can take the USMLE. Some do not, Some have a limit, but if you have a license in another state they will give you one. In some it depends on whether you're an MD or DO. Being flexible about moving to a state without a limit would be a huge plus.
If you apply for a license in a state with a limit and they deny you based upon that, then you can take that denial and apply to retake S1 and S2. You won't need to retake S3 again, assuming you can pass S1 and S2 within 7 years of your S3 pass. Then, you might get a license.
But in any case, a state board may see your 7 year hiatus and decide that you need re-entry training. You'll then need to find a way to meet their requirement -- often at great financial and time cost to you. They may insist on another year of residency. Or on one of the commercial physician re-entry programs. It's totally up to them.
Assuming that's successful, you now have your license. Now you'll need a job -- and whether employers will hire you with a 7+ year gap (since all of the above may take 1-2 years depending) is anyone's guess but I expect they will be hesitant. The honest truth is that you learn about 50% of what you really need to know as a physician in residency, the next 25% in your first 6 months on the job, and the last 25% over the rest of your career. You'll likely have lost much of that 50% you started with.
You could open a private practice, although you will need med mal insurance and that could be difficult. But maybe less so in psych.
