Gratitude doesn't come naturally to most people in the west because of the expectations they are constantly being exposed to by the culture: freedom from all debt is highly valued (not only financial), advertisements generate want (often through entitlement), the media focus on wealth, celebrity, and achievement, the focus on career instead of character, etc. In our culture, which treats good things in our lives as products or our own doing, but the losses and suffering as not our fault, it is a set up for a lack of gratitude.
Your question (as it is now) reads as though you think it's too late for you to learn gratitude (I may well be wrong, but your focus is on your disappointments.)
To help your child, you first need to help yourself so that you experience real gratitude; then you can model it for her every day in your life. If you try to teach something you don't really have, it's not hard for anyone who lives with you to figure it out pretty quickly and reject the words which essentially amount to "do as I say, not as I do".
I have seen people expecting very little from life and be happy for what they have.
What strikes me immediately is that this statement is written in the present tense. That's really the place one must emphasize to find gratitude.
If you want to help your daughter be grateful (and this is best done with modelling from her parents), emphasize and prioritize things she actually has control over: teach character instead of achievement, resilience instead of success, process rather than product, actions over appearance, kindness above self-fulfillment, value people above money, appreciate living in the now rather than anticipating future happiness. One can enjoy life while working to better one's circumstances; if circumstances don't change, one can still enjoy life.
I would recommend that the first step for you (I am assuming she is still very young) is to read* and start keeping a gratitude journal. The focus in gratitude is to see good things in your life now as "gifts" (as opposed to rewards you've earned or deserve): being grateful for the gift of a beautiful sunset, the gift of an opportunity to help someone in need, the gift of a fun experience with your daughter, the gift of a meaningful story in a book, The gift of living with enough, the gift of people you love to share your life today with, etc. The idea is that more you realize your blessings, the more you'll share these feelings with your daughter, and thus shape her attitude by example.
Once you really learn how to see and appreciate all the good things in your life, you can really instruct your daughter in the art of the same.
Sorry if anyone finds this preachy. It is something I'm fairly passionate about.
*I've learned a lot from the writings of a man named Jon Kabat-Zinn. Kabat-Zinn got his Ph.D. in molecular biology from MIT. While at working with cancer patients and others with serious diagnoses at the University of Massachusetts Medical Center, he developed an approach of mindful living. If he could help those in dire circumstances to find happiness, I wanted to know what he taught his patients so I could give it to my own patients. What I read made my own life better as well.
Counting blessings versus burdens: An experimental investigation of gratitude and subjective well-being in daily life.
Gratitude and well-being: A review and theoretical integration
The Psychology of Gratitude
Meditation and Positive Psychology
Wherever You Go, There You Are by Jon Kabat-Zinn
He who receives a benefit with gratitude repays the first installment on his debt. - Seneca