Somewhat like WhatHappened, I see myself as capable of being poly, in that I can be in love with more than one person without my feelings diminishing. I recognize that not everyone is capable of this. Falling in love with TGIB, however, was a surprise. I certainly never planned or looked for multiple loving relationships (beyond FWBs), and if either of my current relationships were to end I don't know that I'd ever be in a polyamorous relationship again. We did not do poly counseling, but worked through it ourselves. Luckily I have an amazing husband who is very open-minded and can wrap his head around people being the way they are even if he is not that way himself. Our situation is also different because TGIB is long-distance. The few times a year we get to see each other in person, it's understood that I will spend more of my time with him (though I make sure not to neglect MC completely). The rest of the time I rarely have to choose, since I can hang out online with TGIB while MC is at work. When I do have to choose, though, I agree it's difficult. There's always a little bit of guilt, but I try to remind myself that they both have lives outside of time spent with me, and that though they each have to deal with time I spend with the other, they also both then get time and attention devoted just to them. It's all comes down to balance, and making sure everyone (including YOU) gets the together time AND the alone time they need. And remember that it's not ALL on you as the hinge to keep everyone happy. They are just as responsible for asking for what they want or need, and you have every right to ask for your own wants and needs from them (sometimes the arms of a V get a pass from the hinge because "they're being so great about sharing me". this seems particularly common when one or both of the arms have no other partners besides the hinge).
Pan Female, Hinge in a V between my mono (straight) husband, Monochrome and my poly (pan) partner, ThatGuyInBlack