ok here are the factors specifically tailored to your case
1) 56y/o
2) groin pain when walking or standing
3) only one side ( one groin not both)
many groin pains for your age group is mistakened for a muscular strain etc but in fact they are actually one of the most consistent symptoms of osteo
arthritis.
based on the 3 factors above , its a classic textbook definition of symptoms of hip osteoarthritis
best course of action to do is to have the xrays taken first
(pelvis ap xrays, frogleg xrays) i have specified there the best xray views to diagnose your problem. you can write it on a piece of paper and show your doctor next time.
treatment for these problem once confirmed:
1)wt loss -better than pain meds , it unloads your hip joint as a consequence of you being lighter, so that when you walk or stand itll hurt less
2)
physical therapy - to promote joint fluid circulation, stronger hip muscles decreases the
stress that has to be borne by the bony hip joint.
3) viscoelastic injections - if the symptoms are that bad but the xrays arent so bad you can try these
4) total
hip replacement - when all else fails, but this isnt recommended for you as of now
merry christmas :)