Friendship vs. relationship?

My bff is a guy. We've been friends for 3 yrs and are basically like brother and sister. We can tell each other anything and we have many of the same interests. There is no romantic interest btwn us. Every guy I date has an issue with my friendship and suggests that I need to change it or put an end to it. Things with the guy I'm dating now are starting to get serious and he recently voiced his objections and stated that in a relationship your partner should come first before all else, even friendship, and that he feels it's time for me to distance myself from this bff. I don't think it's fair to abandon a friendship just to coddle someone else's insecurities, especially when that friend has never wronged me, and trust me I've been stabbed in the back by many friends in my time. He asked how I would feel if the roles were reversed. I don't know the answer to that but I've been friendly with my bff's girlfriends and they've seemed accepting of our friendship. Our friendship is out in the open, there is nothing secretive to be suspicious of. All my bf's have implied my bff is just hoping to "get some" which is almost hilarious bc he's def not hurting for attn from women. Not to mention it seems a little uous since I see him as a brother. It's kind of an insult to me, like being told my only value in this friendship is for what's btwn my legs. I mean, I have a lot more to offer as a person. I'm not a naive kid, I'm an educated 31 yo woman. I know how it may look from the outside, but that's not how it actually is. If some guys would get past their insecurity, I think they could see that. How do I manage both friendships and relationships without giving up on either? Am I asking too much?