We all have them - those that are difficult to love. Sometimes it's the result of sin within our own hearts, while other times it can be the result of being sinned against. Either way, loving as Christ loved us is how we've been instructed to live.
Love isn't primarily something to get.
Love is an offering to give.
How love is practiced can vary, but it always starts in the heart. When Jesus talked about loving enemies, He gave instruction to pray for those that persecute. Why? Maybe loving your enemies begins with genuine prayer for them because "prayer does change things, all kinds of things. But the most important thing it changes is us," (R.C. Sproul).
Notice that we aren't asked to pretend a troublesome situation is "fine" or that a wrong is "right." We are asked to follow the Shepherd and trust Him.
Think of those you find challenging. Ask God to help you give a love offering today - to pray for them as you would want someone to for you.
"For if you love those who love you, what reward will you have? Don’t even the tax collectors do the same? And if you greet only your brothers and sisters, what are you doing out of the ordinary?"