So the cast: I (30F) have divorced parents (58M and 54F) as well as a younger sister (26F). My parents divorced 5 or 6 years ago, when both me and my sister were out of the house.

Mom is now in a serious relationship with someone else who is in his early 40s. We've joked a little bit about her "robbing the cradle" but honestly it's all fine, the guy is really nice and seems to have his shit together.

My dad was dating another woman for a couple years who I really liked. Then she moved out because she found out that my dad was talking to other women online. Basically it sounds like (piecing together both of their stories) she gave him the ultimatum that they needed couple's therapy or else she was leaving, and he agreed to therapy but was being evasive when it came to scheduling appointments, so she got frustrated and moved out.

Now my dad is "seeing" this woman from the internet... Who is, according to his admission, 25 years old. My dad's ex said that she'd seen the chat logs and that the girl is actually only 21, but I can't 100% verify with no evidence. I don't need evidence, frankly, because I think my dad dating someone younger than his youngest daughter is gross no matter what. But then, here's the kicker: my dad's new girlfriend doesn't even speak English, because she's from Colombia.

I live a few hours away, so I'm home sort of often. I stayed with my dad for a few days over Thanksgiving, then a couple days near Christmas, and I also went home the last week in March to visit for about 4 days. All of these times, my dad would disappear into his room in the evening to talk to his girlfriend for hours, and I can very clearly hear it through the air vents... They're not having any sort of meaningful conversation because it all has to go through a translator. They basically just go back and forth with "I love you" "I miss you" "you look pretty tonight" and so on. I don't think I would be this irritated if the girl spoke English, but the fact that she doesn't ruins the validity of his claim that "age is just a number and we have sooooo much in common". So far all he's been able to tell me is that they like the same music.

He's tried a couple times to tell me about her, and once when she called him on the phone while we were out shopping together for Thanksgiving, he tried to pass the phone over so I could introduce myself. I said absolutely not, I'm uncomfortable and she's not even family so you can't use the "oh but it's thanksgiving" excuse. He says that I'm being racist and age-ist, and that I'm hypocritical for supporting my mom's new relationship but not his. I believe STRONGLY that a relationship between a 58 year old man and a 25 year old woman is fucking creepy even in the best of scenarios, but when she only knows like 20 words of English, I can't take it seriously at all. I don't want to hear about her, I don't want to talk to her, and if he ever makes the attempt to meet irl, I want no part of it.

AITA?