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The most likely cause of your pain is that it's due to low estrogen after menopause that causes the vaginal tissues to be very thin and fragile. This is a common problem after menopause for many women.
I would recommend that you see your doctor for an exam and then probably a prescription for estrogen vaginal cream. By using it nightly for 2 weeks, you'll thicken your vaginal tissues to almost where they were before menopause. Then it can be used as needed to maintain, perhaps twice weekly.
There is virtually no ill effects from vaginal estrogen, since the effect is local and little gets to the rest of your body.
An exam is important to be sure there is nothing else causing the pain with intercourse. Best wishes.