So I see where you're coming from. If your group of friends can collectively address all your needs, you would really feel like you don't need a romantic partner. And maybe you don't, which is perfectly fine.
I don't know where you are in your life. Personally, I'm in my 30s, and I've had close friends that have come and go. I grew up with making and losing friends constantly like any kid who had a military parent. All of this is to provide a bit perspective for when I say that (at least in my experience) friends don't stay. There isn't a reason for them to put you first in their lives. As they get more involved in new or existing relationships of their own, romantic or otherwise, there will be drifting and shifting of priorities. And unless you're really good at making friends, it gets harder to make friends as you get older.
A romantic partner is supposed to put you first on that list of social priorities and for a very long time. And it's that feeling of counting on someone to be there for you when you need it that provides a sense of safety and comfort when your overall social network changes.