The reason the game does this is because you have contextual comms turned on. When this option is turned on, the output voice line changes based on what you're aiming at. So if you're aiming at a teammate when you use the Group Up comm it'll send either "I'm on my way" or "I'm with you" based on how far the teammate is from you. Likewise, the "Come to me for healing" is a contextual voiceline that triggered because you're aiming at a teammate that has lost some health.
It seems in your case, you actually may prefer to turn this option off. It's in your communication settings.