@skiah22 and @bkruppa and others. There were many suggestions for coping with sitting pain in old threads, above. Mine has gotten much better thanks to stretching, exercise, MFR and I found a therapist that used intense ultrasound while he does active release stretching. Recently, I've started taking some enzymes (serrapeptidase (biomedic labs) and Nattokinase (Doctor's best); both from Amazon) and these helped immensely. I believe these help the tissue remodel (compression from MFR isn't the only way to remodel the fascia - electrical (galvanic) stimulation, ultrasound, stretching, exercise can assist this process, too). However, I had a lot of stiffness and I do believe it is from deposits of fibrin in muscles, on nerves, on bursa, etc. My pain level (and stiffness) is way down after taking the enzymes I mentioned (on an empty stomach). If you are not on blood thinning medication already, it might be worth a try. That seems to be the contraindication. Also, for some reason 10-15% of Especially if you have stiffness, too. I believe that now I am mostly dealing with healing of tendons that attach to the ischeal tuberosities - hence I have some small sitting pain (which has been getting better over time). Here is a review I wrote for an enzyme product on Amazon:
Long story short I was having some myofascial pain (stiffness, sitting pain) in the legs, glutes, lower back. It’s been getting better thanks to various supplements (especailly Vitamin C with citrus bioflavinoids, quercetin / resveratrol, stretching and exercise). I also had plantar fasciitis in the feet in the past as well as some sciatica symptoms (which is due to some type of nerve compression / irritation somewhere along the nerve).

This helped along with taking nattokinase (200 U) and I worked my way up to 2 tablets of the Serrapeptase 3 times daily (one dose with the Nattokinase) Eventually, I’ll cut back to a maintenance dose and maybe use just 1 of the 80,000 U serrapeptase and 2000 U nattokinase.

While speculative, deposits of fibrin may be the culprit in causing tissue stiffness and improper tissue remodeling as you age. This may accompany (or possibly cause) conditions like plantar fasciitis, phlebitis (and some leg swelling), stiffening of the tissue - all things I am encountering. I noticed a decrease in sitting pain (i.e. less glute stiffness) right away within about four days of starting serrapeptase. On higher doses, I occasionally felt tingling in my feet while walking – but not in a painful way. More like the itching a healing wound might have. I had some areas near the ischial tuberosities that had dense areas that possibly were scar tissue-like (many years of martial arts with kicks, plyometric moves, hard landings probably contributed with this as well as possibly abnormal amounts of fibrin that were deposited on top of that as I aged – that was suggested to me by an injury massage therapist who specializes in aging athletes). Over several weeks, these became smoother and less ropey feeling. Prior massages including aggressive trigger point massage could not remove this / smooth this out. I’ve done all kinds of stretching, exercise and massage. These enzymes have been one of the most effective treatments in healing what I’ve got. Once I started on these enzymes I could feel the difference within a couple weeks. I could see some more recent scars that I have that were raised up appear flatter and remodel.

I generally research what I take and also read all the reviews from people taking these products and also scholarly articles. Based on what I’ve read, (and this is speculative – I can not state any of this as a universal medical certainty) it is quite possible that Serrapeptase can assist tissue remodeling, help remove / minimize scars / adhesions / help break up cysts, etc., including those that may irritate nerves, too. For many people, poorer healing may accompany aging. I believe this enzyme helps healing. I had no gastric irritation from either the 80,000 U version of the 260,000 U version of the enzyme. I was not recompensed in any way for this review. At some point, I'll drop down to a lower maintenance dose with the 80,000 U tablets, I suppose.