Many people simply can't believe that the Lord loves them. Others believe that He loves them, but only when they are pleasing him in some way. Why is it so hard for us to accept His unconditional love?
One reason is that we have a hard time loving others without condition. We might say the words "I love you" to our spouse, children, friends, or fellow believers but all too often are calculating in our mind whether or not they've lived up to our standard. We sometimes excuse ourselves from loving certain people because their behavior upsets or annoys us. The fact that we place restrictions on extending favor causes us to wrongly assume that the Lord does likewise.
Another reason is a poor self-image. Considering ourselves unworthy, we refuse to accept God's love. you know what? None of us are worthy of the heavenly Father' goodness and mercy - so you can let go of that excuse once and for all. We're not coming to Him based on our worth. Rather, we're coming to Him based on his grace, and our position is secure in Christ. To put yourself down as "beneath His grace" is to trample on His loving, generous gift. God arranged an awesome way for us to be reconciled to Him, and His greatest desire is for relationship with each of us.
If you feel unloved or struggle to accept yourself, ask the Holy Spirit to reveal the truth of our heavenly Father's love for you - and to sink it deep into your heart. Receive the truth He reveals. You'll find it's a refreshingly different story about your value as an individual.
Stanley, Charles F. "Accepting God's Gift of Love." In Touch: A Publication of In Touch Ministries. Atlanta, Georgia. February 2015. page 52.