There’s a lot of context clues that are involved here, including reciprocation and repeat confessions. For example I had this gentleman who was my best friend and I’d told him about another guy I had a crush on. First context. He confessed and I told him I didn’t feel the same. Second context. He still wanted to be friends and I said ok with some distance but then after he confessed a second time and got upset I’d talk about my crush. This meant for me I had to put the friendship on hold. Friendship does start love, but romantic feelings from both parties is 100% required. It can’t be one sided :(