You are doing lots of things correctly to help your daughter better manage some of the negative emotional experiences she will be exposed to during childhood and adolescence by allowing her to directly experience healthy activities that build her self esteem.
I'm glad you tried the karate class and it is also good she decided she didn't like it
and wasn't forced to continue it. This was still a good learning experience for her i.e., to discover that she can try things, not like them, and move on to other skills and activities she can discover she likes.
Language classes (Spanish) are a wonderful idea, as is the swimming you mentioned. If she is at all athletic, perhaps she would like to try a team competitive sport or something more 'individual, such as diving, tennis, etc. Again, all of these are the sorts of things that will help insulate her from some of the harmful exposure to things she might otherwise experience with girlfriends who have a lot of time on their hands to do 'nothing'. That is, I suspect that her little girlfriend whom she visited (and probably exposed your daughter to unhealthy video material), does NOT have parents who are engaging her in the sorts of things you want your daughter engaged in. So this girl watches too many videos, has parents who don't really care what she sees and internalizes on TV, etc. This little girl will develop less than healthy values about such things as how to manage anger, how she can be treated by men (aggressively, and with disrespectful sexual behavior), etc., because this is the sort of video material and behavioral values her father models in her home. Too bad for this little girl.
I have a feeling that if you simply continue to be a very good listener for your daughter, communicate to her understanding and keep engaging her in health activities that strengthen her self esteem, she will be just fine going forward. The negative experiences you described in your first post will fade from her memory. You have a daughter who sounds as though she was born to be somewhat more sensitive, anxiety
-prone, emotionally reactive, etc., than other children. So self-esteem building activities are really important for such kids.
I hope this information has been helpful to you. Please let me know if I have overlooked any aspect of your original question. Please click on the green Accept button at the bottom of the screen. Thanks.