So what if they get upset? That's on them! You're not responsible for how they choose to react. You are responsible for your own well-being and emotional health, however. Bottling up all your hurt and feelings of loss will not do anyone any good. There is no good reason to set your own needs aside and defer to others just to appease them by "keeping quiet." They've all got to do some growing up -- it isn't kind or helpful to shut you down every time you try to express yourself. All of you need to talk, talk, and talk some more, if you all want a healthy poly tangle.
The world opens up... when you do.
Oh, oh, can't you see? Love is the drug for me. ~Bryan Ferry
"Love is that condition in which another person's happiness is essential to your own." ~Robert Heinlein