my dad is talking to a girl around my age

context: my mom is getting her teeth put Back in and she is sick rn. i try to take care of her the Best i can as well as clean the house. my dad cares but not really, he's not home most of the times (work). and when he is home he just eats and yells at me for being a "grown woman" (im 17) who doesn't clean after him.

me n my mom were sitting in the kitchen w my dad there too. she threw up minutes ago and was soBBing in my arms while i held her head. and my dad just showed us his phone and told us that some Beautiful chinese girl had wrote him.

i just stared at my mom and she stared Back at me while my dad was telling us aBout that girl. (i think she's a scammer, But who knows). he told us about how she looks like a model and how she makes fashion designs. told us he was talking to her. to his sick wife and his child, mind you,

i told him he was awful for telling us that. that mom was sick and he was Being insemsitive.

"well, you talk to other boys!" huh???

yeah. cause i don't have a wife and children? tf??? 

i then lowkey spied on him. he was asking her if she was married, if she was travelling a lot or no. he send her his picture and she replied saying he looks "like a polite gentleman". sent him roses and he sent her smiling faces.

and i am so grossed out. my dad is 54. she's around 20. we are roughly in the same age group. the idea of my FATHER talking to a girl in the same age w people I STUDY WITH, people who i think like of my equals makes me SICK. i can't talk to him. i'm also very scared he'll get scammed and that will affect me n mom too. i am deeply disturBed and i genuine;y can't even look at him the same.