Have you been lifting for awhile or are you new to it? Does it hurt while you lift or afterward? Are you in the most pain first thing in the morning, or does it gradually come on throughout the day?
I dealt with a very similar issue for several years — pain right at my SI joints on both sides that ranged from a sharp, needle-like pain to a deep ache. Couldn't sit and couldn't lift without pain. I was a novice lifter at the time and was desperate to train, so I tried EVERYTHING to get rid of it: physical therapy, chiropractors, spinal surgeons, steriod injections, MRIs, rheumatologists, lifting, not lifting. I don't mean to scare you, but I even had a rheumatologist diagnose me with ankylosing spondylitis and that freaked me out for a few months before a second rheumy said I didn't have it.
Nothing changed until I got a Starting Strength coach to look at my lifting form. I did that through Starting Strength Online Coaching (which I still do), but you could easily do it on this very forum for free. I was *absolutely certain* I was doing the lifts correctly until my SSOC coach looked at my videos and I learned my spine was wayyyy overextended on every single lift (except the bench, oddly, when you actually want more extension). There were other problems, of course, but the overextension was the real pain trigger. It took me a few months to clean that up, but six months after starting the program with perfect form, my once-debilitating back pain had decreased almost entirely. If you're a novice lifter and you've never had a coach look at your lifts, it's worth doing that. And get an honest-to-god Starting Strength coach deeply familiar with how you're trying to squat. I got messed up by otherwise-competent lifting friends who dind't know the method.
I still get pain down there sometimes, but I don't panic and trust that it will subside. It always does after a day or two, and it never interferes with my training. If you want practical stuff: When it really tightens up on me in the gym, I do some moderate foam rolling, mashing the very very top of my butt (the meaty part of the ass just distal to the tailbone) and along the underside of the pelvic girdle. That usually does the trick. I also avoid carrying things in front of me as much as I can: opening windows can give me little tweaks.
Since you asked about whether it's a chronic problem, you need to read this article immediately, if you haven't already:
Aches and Pains | Austin Baraki. Parse every sentence, read every footnote, and click every link in every footnote. This piece was a gamechanger for me. You are not broken, and you will lift again.