I'm such a terrible person 😭😭😭😭

Gracie!!! 💄👛👠 • In Love ❤️,
     I love my fiancé with all my heart. But our relationship is complicated. We aren't the "regular" couple. We can't go out, to restaurants, movies, no where. We've been like this for 3 years. He comes to my parents house, or I go to his house.
    I met a new guy, he is so adorable. Such a nice guy. We started spending time together. He tried to kiss me but, I wouldn't kiss back. Idk a part of me knows I shouldn't do it. But another part of me says to give him a chance. I made a terrible mistake by telling him, that I'm single. He asked me to be his gf  but I told him I needed time.
       I don't know what to do. I'm so confused. I love my fiancé and I don't want to hurt him. But sometimes I get tired of him, I feel our love is fading, I feel like I'm just there because I know how much he loves me. &&&  as for the new guy, I feel happy with him. But I'm scared, if I'm with him I would lose the other. What if with him it's just a few months when I had already something serious enough with the other. 
    Sometimes I think, why not both? It might work out for a few months but they will find out eventually. Plus deep down I know it's wrong. 
     Please help me, I need advice. I don't know what to do 😩😭😭😭😞