Everyone you ever love will hurt you.
Well, that sucks.
If we place our hope in that person alone, then yes. The very fact that we are imperfect means that some day, somehow, we're going to disappoint someone. If we think that that person is perfect and expect perfection from them, then...well, you can see where this is going. Know that they try, but know also that it is not the things they do that defines who they are as a person created by God. Our happiness cannot be dependent on how others treat us, or on our expectations of other people. It is a guaranteed fail.
But then, our hearts weren't made to be filled by anyone -or anything- on this earth, anyway.
As much as we want another person to be the one to 'complete' us, the only one who will ever do that - in fact, the only one who is capable of doing that - is God. Father, Son, and Holy Spirit, the perfect relationship of Love, is the only one that can fulfill that longing for true love in our being. Because that's why we expect people to be certain things to us, isn't it? We want them to remember the good we did, to do that thing without being asked, to say thank you. We want to feel loved; to feel like we matter. I don't care if we're talking about your dog, your best friend, or your spouse. To them, sure, you mean a lot. But in the eyes of Jesus, you mean the world.
Don't believe me? Just look at the Cross.
Defining ourselves by what we do, or what people think of us, will never fill the empty space that exists in us to be filled by God. In my case, how well I sing, how many people I make laugh, or how many parish youth events I deem "successful" won't do the trick at all. Christ Himself tells us to "strive first for the kingdom of God and His righteousness" (Matthew 6:33). If you find Him, everything else that you need in life will flow from it. Acceptance. Gratitude. Recognition. Understanding. Love. All mixed in with generous amounts of everlasting life.
That's the reason why we fast from food, from our possessions, from some of our earthly pleasures. To make room for God. Lent is a great time to realize, or re-realize, that Jesus - and only Jesus - can give us "life to the fullest" (John 10:10). So don't wait on others. Wait on Christ.