Feeling Like I Let Allah Down After a Moment of Weakness

Assalamu alaikum, I'm not sure where to begin, but I need to get this off my chest. For years, I was lost in my own desires, and though I tried to turn back to Allah now and then, my repentance never really lasted. There was this sister who seemed just as mixed up as me, and I was so drawn to her that I ended up in some bad situations. But I kept getting the feeling she was only out for her own benefit, treating brothers like tools, and she'd become cold once she got what she wanted. I finally told myself I'd stop chasing her and truly repent, leaving behind all those sins. Things started looking up-Allah opened doors I never expected, gifting me things I love after I'd lost hope. I felt so blessed and close to my Lord. Then out of nowhere, she messaged me. And in an instant, I forgot everything, like I picked her over Allah. I fell right back into sin. This time, she made it crystal clear she didn't really care, we had a big fight, and she blocked me everywhere. Now I'm crushed, not just because I slipped, but because I chose her over Allah in a heartbeat-and it was all for nothing. It makes me wonder: if she hadn't pushed me away, would I have kept sinning? How can I trust my own repentance after this? The worst part is, I turned away after Allah had showered me with so much. I keep thinking of the words: "And you disobeyed Him after He showed you what you love." I want to repent, but I don't feel worthy, and I'm scared I'll just fail again. I'm lost and don't know how to move forward.