You cannot make someone sincerely support something they don't agree with. You may be able to convince them to stop actively opposing it, but that is not the same thing as obtaining support.

Just as you want to be understood, you should also seek to understand. She is the mother of a person that she believes is making a poor choice. She feels a strong obligation to help that person change their mind, and likely nothing you can say will change that feeling. So you and she need to find a compromise regarding the way this issue is raised and discussed, not one regarding the choice itself.

You may have to describe how her behavior is hurting your relationship with her and then be clear about what you're asking her to do, such as to stop making comments that criticize your judgement or that hinder your appreciation of her company. You have to avoid making her defensive; use sentences that begin with "I feel" rather than "You are". Also, you have to express appreciation that she loves you so much as to continually desire to express her views about it. Finally, you may have to remind her patiently many times about the rules of engagement.

If what you really want is for her to play-act like she supports your choice while continuing to disagree with it, I would suggest that you are asking for an unreasonable accomodation on her part.

You cannot make someone sincerely support something they don't agree with. You may be able to convince them to stop actively opposing it, but that is not the same thing as obtaining support.

Just as you want to be understood, you should also seek to understand. She is the mother of a person that she believes is making a poor choice. She feels a strong obligation to help that person change their mind, and likely nothing you can say will change that feeling. So you and she need to find a compromise regarding the way this issue is raised and discussed, not one regarding the choice itself.

You may have to describe how her behavior is hurting your relationship with her and then be clear about what you're asking her to do, such as to stop making comments that criticize your judgement or that hinder your appreciation of her company. You have to avoid making her defensive; use sentences that begin with "I feel" rather than "You are". Also, you have to express appreciation that she loves you so much as to continually desire to express her views about it. Finially, you need to work with her to come to an agreement concerning the rules of engagement for this topic, and you may have to patiently remind her many times of that agreement. At all times, you should act in love.

If what you really want is for her to play-act like she supports your choice while continuing to disagree with it, I would suggest that you are asking for an unreasonable accomodation on her part.