You can’t blame someone for walking away if you didn’t do anything to make them stay.
This quote really hits home for me when I think about my ex. I'm going to try elaborating it as well as I can based on my own personal experience, a very recent experience at that. My last relationship was nothing less of a roller-coaster ride for me. She was someone I was deeply involved with and I gave literally everything I had to this girl. All of my trust, all of my love, all of my time and attention, you name it. It was very passionate for me, most of my friends used to tell me I'm going overboard, but I didn't care as long as she had a smile on her face.
A year later, I found out that she cheated on me. That was the first day of the rest of my life. I changed. I changed into someone I wasn't, someone I never thought I'd be. My entire world shattered around my eyes and I couldn't think straight, it took its toll on me and I took a good while to recover and come back to normal. So, coming back to the quote, it talks about people who blame someone for walking away even after they honestly didn't do much to make them stay.
When I found out about the cheating, I broke up with her. She apologised and everything but I still walked away. Later on, I found out that she blamed me for the breakup, she had told everyone that I just suddenly stopped loving her and I, myself, let go of the relationship. This is what this quote talks about. A person will only love you as long as you appreciate their love and efforts, the moment you stop appreciating them for everything they're doing for you, they'll walk away and you most definitely can NOT blame them for walking away.
Either be the kind of partner who appreciates even the smallest of gestures, or be a complainer who will never be satisfied no matter what your better half does for you. And trust me, if you're the latter, you'll never find true happiness in life or love.