Hello doctor, im a 26 years old guy. I am in a sexual relationship with a 48 years women for more than a year now. We have developed some crazy attraction towards each other. We have sex almost daily for hours. We try different things like porn and do it. Spitting kissing licking anal everything. However she is 48 and has muscles pains after and during sex also legs pain. Sometimes she can't walk properly for some time after sex. Is this a problem moreover is it harmful to have sex daily also we both want to stop ,however we have not been able to control please advise.