Why i feel difficult to call people out or to stand up for myself
First off let me say I am sorry that you are experiencing the disregard and disrespectful behavior of others. It has its own unique hurt if those behaviors are coming from others thought of as friends. The awesome thing about you is that you are also talking about your own values and what is important you. What matters to you. The chosen qualities of action... of "being and doing". You might even consider that these things that have been occurring could be viewed as the "gift of the negative", in that the actions of these friends that are showing disregard, that are not being sensitive to or judging, might be helping you to understand better and forge the qualities of being and doing that are important and matter to you. Values are personal, values are not feelings, values are not about how people treat us... values are not goals but rather if goals are the destination values are the journey or a chosen direction. Values are the way in which you want to evolve toward.
That being said, it is also important to call out behaviors that disregard and judge another person or people especially if it has to do with their race, ethnicity, gender. It can be done in a manner that calls out the behaviors and not the person. It might also be a time to consider expanding the social circle to include like minded people who can have fun, disagree and also demonstrate kindness and nonjudgemental positive regard.
Another important aspect is to be kind to self and not become self aversive or judgmental on to yourself because you "didn't stand up for yourself". Sometimes we have to see and accept our humanness and that we make mistakes and that we can learn from our experiences. Another strength in you is that you are noticing your thoughts and feelings and this can be important to cultivating a relationship with our minds so that we can see our thoughts and not be our thoughts. Finding our own voice is a work in progress.
In the words of Thich Nhat Hanh, "No mud, no Lotus"... in other words, without being rooted in the muck of our life, we wouldn't be able to blossom into our full potential or as another great wise person once told me ... "Life is like a bowl of cherries... with the pits still in" ... Keep partaking of the cherries Black Unicorn, despite the "pits". Unicorns are said to be powerful and feral, thwarting all brutish efforts to capture them. Be well... be safe... Thanks for reaching out for help and support with your question. I hope you have found something in my response that might be helpful.
Be well... May you find your way safely through this period of time.