Overcoming Guilt from a Past Mistake and Moving Forward in Faith

Assalamu alaikum, I’ve been carrying a heavy burden of guilt over a sin I committed, and it’s making me feel like my chances for a good marriage are ruined. I won’t share the exact details because we’re taught not to expose our sins, but it involved talking to someone online in a way that wasn’t proper or respectful. Alhamdulillah, Allah protected me from letting it go further into major haram, but I still feel so stressed and ashamed that it even happened. I got carried away because I was serious about marrying this person, and we ended up having those conversations. It’s been months since it stopped, and I’ve completely left anything related to lust behind-Alhamdulillah, I have control now. I’ve truly changed, but whenever this sin comes to mind, it haunts me. I know Allah is Ar-Rahman and forgives, but it still hurts to remember what I did. I can’t seem to forgive myself, especially since I knew better. Has anyone else felt this way and managed to move on? It hurts so much that I sometimes don’t even want to get married anymore because I feel like I’ve betrayed my future spouse. Would most people see this as a dealbreaker? I always dreamed of marriage and building a life with someone, but now I fear that future is lost because of my past.