I've been dating my girlfriend for six months. She's a very nice person and always goes out of her way to make everyone feel happy and appreciated. She's kind no matter what others do/say to her.
She's a fairly sociable person and our relationship is well-known. People often feel the need to give her their opinion on me/us. She usually ignores them and responds passively. However, this has crossed the line a couple times, in which other men have insulted me to her (over text), such as:
You know, I've never liked your boyfriend. You should break up with him.
(response) Surprise... and I don't really know.
Another example:
You're way too good for him, he's a gross P.O.S. You deserve better, especially with that body.
(response) Yeah I know. And thanks.
When I asked her about previous similar messages/chats, she said she was just letting them think she agreed to avoid confrontation and keep a friend. But I wouldn't want to be friends with someone who thought that way about my SO. Furthermore, I have no way of knowing that she was really lying to them; her texts did seem authentic and the people were convinced that she didn't have real feelings for me.
Should I just accept that we're different and that she'll tell others whatever they want to hear, while in reality she is happy in our relationship? Or am I right in getting worried about her reactions to their comments? I don't like her letting others walk all over me (or compliment her about her physical appearance, which just doesn't feel right).
How should I react in this situation, with the intention of continuing this relationship, but not at the expense of my self-esteem or having the risk of being cheated on? I love her but I don't want to be in a toxic relationship in which she goes behind my back and tells lies. What do I do?