My girlfriend is uncomfortable with a close female friend of mine. What should I do?

My (29M) girlfriend (26F) and I have been together for about 4 months. Things are great so far and we get along well. However, our only thorn in the side has been about my female friend (27F). I met my friend via a dating app 3 years ago but there was never anything romantic and from the get go, things have always been platonic. My girlfriend is aware of this as I told her to be transparent.

My girlfriend's main issue is that my friend and I have daily interactions via text. I'm not talking every minute, every hour; but a continuation of a conversation about my friend's boy problem, cat, and random stuff. And I mostly text when I'm checking my phone for anything (emails, messages, etc.). My girlfriend said she believes there's this attachment or dependency which I disagreed with. I communicated to my girlfriend that if my friend ever did anything that crossed a boundary, I'd address it and wouldn't excuse it. But she believes that out of respect, if her close male friend got into a relationship, she'd talk to them less. While I understand that, that's not who I am as a person as I don't believe in changing the way I interact with my friends because I'm in a relationship unless that friendship was toxic, the friend was compromising our relationship, etc. To me, it feels disingenuous towards my friendships. I told her as well that if my friend lived in the same city, I'd much rather prefer to catch up in person but because that's not physically possible, we text. I hear her and understand my girlfriend's points and I do reassure her the best I can but this issue comes up every week and it's becoming difficult to be patient and understanding.

When I told my girlfriend that, she said she felt like I was invalidating her. I've clarified all the interactions I've had with my friend, all of which didn't cross any boundaries. I'm just not sure what to do at this point.

TL;DR: My girlfriend is uncomfortable with a close female friend of mine. I've heard her and understand her points and confirmed boundaries were not crossed but it's become a repeated issue in our relationship.

Edit: Thank you for the replies! It's all been very positive and I appreciate it all. After some thought, I do think I'll try to gradually reduce the amount of communication with my friend. Although that may take time as I want to do it "naturally", i.e., not suddenly stop texting, I do think it'll be best. It's early on in my relationship but my girlfriend is a great person and someone I can foresee a long term relationship with!