I am a 27F, daddy’s girl if you will. My parents divorced when I was 13. Dad (53M) has been with the same girlfriend (55F) this whole time, her name is Susan. Susan and I never really bonded but I was always respectful towards her for my dad’s sake. I did have an older brother, they got along great. To the point where she was in awe of him. When my brother passed away in 2022 from an overdose. Things went down hill on my brothers 1 year celebration of life that I planned with my Dad. Susan had a horrible time and started a fight with me cause she wanted to plan it which then she blamed me for his death and stated she’s hated me since she’s met me. My dad heard everything and told me in the heat of the argument people say the worst things they don’t mean. Time has passed since that happened, I put alot of space between me and her to the point where we do not talk. This year on my birthday April 6th , I went to visit my dad. My dad asked me to say hi to Susan but I did not feel comfortable doing so. Susan made a scene cause I wouldn’t say hi to her but I feel like she owes me an apology before we go any further. Dad yelled at me at the top of his lungs to drop it and took her side. My dad said “If you can’t be nice to her than get the fuck out“. I feel like I’m on the back burner and my dad and I haven’t spoken since my birthday. AITA for not wanting to be nice to my dad’s GF of 15yrs?