do trios ever work?

i’m in a friend group with a pair of childhood best friends and throughout the past decade, i have occasionally felt like the 3rd wheel.

ofc i understand that their bond is deeper than most people’s and that i’ll never the able to reach that bc of the time they’ve had together and the experiences they’ve shared, but i find myself getting hurt just by reflecting on it.

they’re not outwardly exclusive, but the way they react to each other’s problems or feelings is a lot more intimate then mine. for example, if i open up about something, one of them is usually overly supportive and positive (it feels like when someone says they’re sad and the other person tells them not to feel sad bc they deserve to feel happy), and the other will either have no input or agree. however, when they share their problems, it’s like a switch goes off and they go so much more in-depth.

they also talk about things in front of me and i feel awkward sitting there waiting for them to finish, they argue like how best friends would while im sitting there waiting for them to finish, and they just gravitate towards each other and consider each other more than anyone else.

im not saying they’re bad people or friends; they are good people and i know they care, and i dont always feel like this and there are good moments. however, i feel like im an extra person at times i find myself being unsure of whether or not i want to hangout with them bc im almost anticipating leaving the hangout feeling like i wouldve had more fun if i stayed home.

overall, i understand why it is the way it is, but im just wondering if it’s even worth trying and putting in effort when i know i’ll never mean as much to them as they do to each other, and they show me that (despite it probably being subconsciously).