If it's truly in your groin area... is it inside the pelvis, or closer to your hip bone? Bones are bones, and soft tissue is soft tissue. Do you have a fibroid tumor? (harmless tumors that grow off your uterus) This will cause that!

I have had this problem for many years.
It is in both groins.
My tendons in both groins are as tight as rocks.
If I forget to "stretch" before biking or walking on treadmill, I feel the pain in my groins and thighs all night and into the next day. I had an opportunity to have the
Tendons spliced when I was younger but I was afraid my legs would be flopping every whichway.
Now that I am older I think it would have been a good idea. I have similar problems with both feet... tight fascia and heel spurs. Better with stretching.
The best stretch for me is to lay on my back with my butt up against the wall and open my legs as wide as I can for 30 seconds. My heels up against the wall for support.
I hope this helps you.
I must confess that my groins still let me know that they can become a problem if I am not giving them special attention.

I used to be so flexible that I could do all sorts of splits. About 3-4 years ago, I started getting groin and glute pain when I walked or hiked. It got worse and worse. During this time, I became less and less flexible too. Then I could no longer move my left leg out to the side more than about 6-8" or I would get a horrific snapping pain, then soreness for hours.

(Oops, submitted answer before I was ready.) I've had x-rays and they show some hip osteoarthritis. Physical therapist agreed that was the issue. Groin pain typically means hips, she told me. BUT, I believe this is more tendon/ligament related, then bone related & I'm going to research that. I've been trying to stengthen and stretch my hamstrings, glutes and quads, but I admit it feels somewhat futile. Whah!

I had the snapping the popping, the pain, the groin area pain and all of that. Once I had the surgery to repair the torn labrum (that by the time I found someone who knew what was up it disentegrated and couldn't be repaired) I am much better. They snipped the tendon a little bit to lengthen it which took a LONG time to heal, but now that I've had all of this done, I no longer have pain. Ask about a torn or ripped labrum.

I have the Same popping & snapping in my groin... feels like my groin is separating and my leg is about to come out of socket... painfull and scary.
The human body is a mess of things that can go wrong.

I've read through all the responses and I don't have the pop but I sure have the same symptoms described in the first question. Mine just happens suddenly and the pain is so intense it takes my breath away. I can't lift my leg to walk and have to slide my foot to get to a place to sit down. Sitting doesn't make mine worst, it actually helps relieve the pain. I was wondering if the tendon was slipping out of place or something like that and sitting down reset it.