If there is one thing I have learned in life..it would be that without communication there is no relationship, whether that be friendship or love. If you can't completely tell someone you trust everything that you feel inside and have them acknowledge that, then they are not worth your time. I have watched many relationships and friendships fall through because of the fact that one person gave and the other could not give back. I expect in my relationships with anyone that they can come to me, and that I can go to them in a time of need.. I wish this was always true in the friendships that I hold. I know for a fact that you cannot be in "love" with someone without being able to fully communicate, and unfortunately I've first hand witnessed this over and over again in my surroundings.
Everyone feels differently about "communicating".. but in my personal opinion, communicating is being able to talk things through, tell that significant person everything that your heart desires without feeling stupid.. & knowing that they will understand you and comfort you all that they can.
Once you've found this, you'll find it hard to go back to a noncommunicating world..