There is a lot here to answer. First adultery is an act that only a married person can commit. When I person says vows to forsake every one else and only have eyes for "you.' that is a sacred trust that shouldn't be treated lightly. Sometimes a relationship fails and those mutual vows are given up. Sometimes by mutual consent they change somewhat.
The key is honesty in a sexual relationship. Your mother didn't teach you about being responsible and what it means to when you are ready to make a true commitment. So when you determine not to follow her set of conduct rules, you are left basically with none.
Your age is very important. If your are 17, she can call the shots and get away with it if she is willing to pay the price and suffer the consequences. If you are 18 that changes every thing. However, if she controls the purse strings, then you may have a choice: Go by her rules or the money is cut off.
Now I don't like threats like that. But parents do them all the time. I hope your mother isn't that way.
If you think your mom will listen sit down and talk with her. Only you know what she will and will not discuss and how she will react to it.
First, no one has a right to force a person to tell about their sexual activities. Even in the rape of a seven year old child, we the professionals have to wait unitl the child is ready, Never, would we tell a seven year old that he can't get out of the chair to go to the bathroom, get a drink, eat a meal, or sleep until he told us what happened. That just is inexcusable.
It is inexcusable for your mother to expect you to give the details of your sexual activities against your will.Had your mother built a level of trust and respect about sex while you were growing up, it would be different. But she didn't. It may be too late now. But maybe not. Listen carefully and see if there is a change.
As for your new sexual freedom, you haven't told us exactly what you are in to. Let me give you some basic suggestions that most people would agree that they are correct. Some would want even stricter rules like wait until marriage. But I think this list is good. If others see something I left off, do comment as I don't claim to be perfect in making the list that is totally perfect.
1. Do not engage in sexual activity you don't want to do. Don't do "it' to get back at someone or just to pelase someone unless you want that relationship.
2.Be honest with your partner. If your partner is to you just a fuck buddy, then be sure that person knows that. Don't lead him or her along. If you want a real long term committed relationship, sooner or later you will need to convey that to the other person or the relationship will derail.
3. Don't have sex with a person who is not legal in your state or with a person who is not truly consenting. If there is doubt, don't!
4. Practice the safest sex possible always 100 percent of the time.
5. Avoid getting drunk or on drugs to do things you wouldn't doing sober. If you aren't willing to do them sober, then don't do them drunk or under the influence of some drug.
6. Never change your CODE OF CONDUCT in the middle of a sexual encounter. Wait until the next day when you are calm and really think through if you really want to change what you think is right or wrong and you are willing to do on a date. If after a time some away from the person, evaluate if you really want to change your code of conduct. The world is full of people who in a moment of passion changed what they thought was their code of conduct and then the next morning deeply regretted what they did.
Here is my personal belief about sex and also my professional belief.
Sexual intercourse is an activity for adults. It is not a child's game. (Under age 15.) Children should not be engaging in making true love. Self masturbation, mutual masturbation, fondling. etc.: We can preach against it all day long. Some will come on here and tear me to shreds for saying this but, it is going ot happen. It has been happening since the beginning of time. It will continue to happen. It is inappropriate behavior in public. That is private and the more adults stay out of it, the better things are.
However, research shows that once a teen becomes active sexually, they aren't going to stop. Knowing that, the best we can do is teach them a code of behavior similar to what I wrote above. Try to see that they don't have sex and have an unwanted pregnancy, ( key word: unwanted.) a disease, or emotional issues stemming from their sexual actions.
Adults SHOULD be there to listen to the kids and not judge them, but be there to help them grow into mature adults.
After 15, it gets tricky. Some teens are adults mentally, sexually and emotioinally at age 15. Some aren't until age 19. If we can keep a reasonable code of conduct out there and a line of communication we may help some teens see that they aren't ready for sexual intercourse yet. When it becomes the teens decision, that is much better than when it is the adult's decision.
Whatever the age, when teens start being sexually active, they should hopefully have a relationship with their parents that they can get the condoms, birth control, etc that they need without parental judgment. Once a teen has had sex voluntarily, that teen has entered the adult world. There very rarely is no turning back.
This idea of if you don't do it my way, you are kicked out of the house is NOT unconditional love. And it rarely works. Only in extreme cases should it be done and then only to protect other children or the parents themselves from a child that far, way far out of control of himself or herself.
Most important is that unconditional love that a parent should have for their child. Unconditional love supercedes everything I have written or anyone has written. If we as parents and mentoring adults fail at giving unconditional love, then we have failed period.
Shame on that mother for demanding to know the details. If she had the right relationship with her child, the child would most likely have shared and even asked for advice. Let the child ask the mother for all the details of her sexual life from the beginning, minute details please. The shit will hit the fan for sure. You can almost always be sure that bringing her sexual past up with cause her to drop her child's sexual past post haste. Most of the time.
To complicate things, this child is an adult's age now. The relationship shouldn't be the same as when the child was 15. Perhaps the mother is refusing to accept that her child is now an adult.
Parents just have to blow it and teens have to get advice from the school counselor who helps every child in the high school and is absolutely fantastic. She only failed with two girls, her own. Even professionals don't always do it right when it comes to their own children.
Good luck. Be very honest with your self and your partner in every relationship. You will be blest if you do.