I am similar in weight and age - 47, about 120kg, but over 2 meters, so my sitting bones are probably further apart than yours. I use a Specialized Power Arc Pro Elaston 155mm saddle. It has a cutout and is rather short. A plus for me was that the saddle drops sharply to the sides so my upper legs don't chafe on the saddle. After some weeks of discomfort and experimentation, I can ride it for 4 or more hours without any issue, having a drop of about 14cm.

Two points where key for me:

An important point was to rotate my hip in a way that I explicitely have my weight on my sit bones. That can be a very strange feeling because you need your core and your back muscles to maintain the position. I lowered my handlebars gradually until I could sit in that position long enough. So I went from having almost no drop and sitting almost straight up to the drop I have now and my perineum is fine now.

The other point was using shammy cream and a good shorts/bibs.