I feel like my father doesn’t appreciate having me as his daughter

Assalamu alaikum, I’m using a throwaway because I don’t want anyone I know to see this. It’s hard for me to open up to people around me about what’s going on. We didn’t grow up practicing Islam, we only started recently after we lost my sibling in a tragic way. It hit all of us really hard. Now that I’m a bit older, I’ve been pushing myself at university and working part-time too. I’ve kept away from anything haram, no relationships or anything like that. My parents have been arguing on and off-years ago, during one fight, my father admitted he wished he had a son. My mother thought it was a silly idea at first, but after they made up, she went straight into trying IVF to have more kids. It didn’t work. My father and mother fight a lot, and over time my father ended up divorcing her by mistake. Recently they realized they can’t stay together anymore. They haven’t told me directly-I overheard them, and my aunt also told me behind my mother’s back because she thought I should know. Anyway, my father now wants to marry again because he wants a son. I feel awful. I don’t get why it hurts me so much. My father is kind to me, but he’s not always there. I miss the dad who used to lift me up when I was little, I miss going out for ice cream just because. I’ve worked so hard to show I’m worthy, that I’m still here even though my brother is gone. I went through so much to get where I am after losing my brother, but it feels like whatever I do, my father will still want a son. I’m almost 21, how is any of this fair? I feel like if my father goes through with remarrying, I’ll lose my connection with him. This is messing with me so much. I managed to ruin a final exam last week because of it, and if I fail, I could wreck my whole degree-it was that important. I just want to cry. Both my parents have siblings they can vent to. I don’t have anyone left, and I don’t feel comfortable talking about my parents to friends. Am I being overly emotional about this?