How do you love? Do you love the way others want you to love? The way you love is highly influenced by your perception of parent's love for you. However, when we express our love, others may have different expectations from you. And hence all the love that you shower on them, gets back-fired, or goes unappreciated. For a change, try and put yourself in other's shoes and figure out how they want you to love them.
Inability to understand other's expectations from you could often be the root cause of difficulties in relationships in spite of giving your best in your own way.