I'm going to butt into my mother's relationship
Why would you butt in your mother's relationship?
I don't want her getting hurt.
It's understandable that you feel the need to protect your mother. However, you should not interfere in her relationship, doing so could lead to her being upset with you.
I'm only doing it to make her happy.
If your mother has not asked you to interfere in her relationship, doing so will not make her happy. You should allow your mother to handle her relationship the way that she chooses to.