Assalaamu Alaikum,
I hope this reaches you in the best of health and eeman sister.
None of us are perfect sister. How many of us have been in that exact same situation as you are in right now? As humans, we do make mistakes and sometimes we make them over and over again. That doesn't mean we can excuse ourselves and let that be a justification to continue doing a sin (which I know you are not doing anyway). But what I'm trying to emphasize is that you are not the only one this happens to.
Sister, it is clear that you deeply regret this sin each time you fall into it. Repent to Allah each time this happens sister. And, repent as sincerely as you can with the firm intention of NEVER going back to that sin. And make lots of Dua to Allah to help you stay away from this sin.
Try to identify what are the factors causing you to fall into this sin? For instance, some people are in the habit of smoking. In that case, evaluate the times and the things around you that are helping you towards this sin. Maybe it is the people you hang out with. Maybe it is the environment. Some people have the habit of masturbation. Again, evaluate what causes someone to fall into this sin. Staying away from movies and books which provokes ones' desire, trying not to be alone in a room etc. These are all steps that can help. So take some time and think about what is causing you to fall into this particular sin sister. Don't reveal your sin to others. Allah has hidden it for you and not exposed you to the world Alhamdulillah. Just figure out the times, places, reasons you are being drawn into this.
Try to seek cures for the sin as well. There have been certain cures mentioned in the Sunnah for certain things. These will really help you In Shaa Allah.
No matter what happens, don't let go of your salaat sister. Salaat is what is helping you stay connected to Allah. Often shaytan tricks us by making us think that our sin is so awful, it is so disgusting, how can you even consider doing salaat? Shaytan whispers these things in your mind and it is a clear attempt of shaytan to keep you away from Allah. Don't let him win. You might be filled with shame and regret. You might feel ashamed and so disgusted with yourself for having done this sin again that you just want to hide yourself. You feel like you are not good enough to do salaat. These are all tricks from shaytan. Don't ever give into it. If you fall into the sin, try to stop it as soon as possible, move away from the scene and do wudu and pray to Allah for forgiveness.
If you do fall into it again and again, give yourself permission to get up too again and again. Be kind to yourself. Try to listen to some short Islamic lectures on the punishments in the grave, about the Day of Judgement etc. In a way, try to shock or scare your nafs so that you find it harder to go into that sin. But at the same time, keep it balanced. Read about the Mercy of Allah. How Allah loves to forgive His slaves. How Allah loves you so much.
It is such a sign of Allah's love that you are guided into this forum right now sister. I came across this forum about 7 years ago at a time when I was very lost and confused myself. I was born into a Muslim family but was not really practicing. It was by Allah's mercy that I came across this forum and it helped me so much and I pray that it helps you as well sister In SHaa Allah.
Please feel free to PM me if you wish to talk further in private as well. May Allah help you sister and I pray that this message benefits you. Ameen.