This song really resonates with me. The meaning I take from this is to not be too proud to admit something's wrong and that you're struggling with stuff. "Shine a little light" on what's troubling you. "You always gave installments" I took as "You always hinted that something was wrong but never went into detail" and "give me full communication with you" is just simply a desire to talk to the subject about what's bothering them.
Don't let pride stop you from asking for help. That's the meaning, for me.