Normal or Wtf!

So I went out with my boyfriend and his friend we’ll call his friend O anyways O invited a girl from work that’s been into him and he’s been into her the issue is O can be little oblivious and a bad texter although in person he’s alright anyways when she left the party he was texting her and he kept asking my boyfriend for advice but what really bothers me isn’t that it’s the fact that my boyfriend is over here texting her every time she texts back to O meanwhile O isn’t other the side it’s my boyfriend texting her back just because O doesn’t know what to write what’s just as bad is I’m watching my boyfriend smiling as he texting her like flirting like honestly I don’t know if I’m crazy for feeling hurt over it because when I got home and spoke to my boyfriend about not wanting him to text for his friend again because it made me feel hurt he said that I was acting stupid about the whole thing and that he’s just helping his friend out but I mean I’m okay with him giving advice to his friend but I don’t think that’s how things should be done how would you feel?