I understand what you're going through. I had obsessive thoughts over people for years and it is definitely not easy to break free. There is some good advice here from other people and I'll just try to add to them and tell you what has worked for me and hope it helps you
When you are in the midst obsessions it is not easy not to blame yourself. You can clearly see this is not a "high aspiration" yet you can't really control it so you start to feel guilty about it. But believe me, you are the only person who can ever get you out of this. It's no other person no matter how smart or great they are and no matter how much they love you. So what happens if the only person who can get you out of the loop blames you for being in the loop? Be careful not to feel guilty about feeling guilty. This is what I did for a long time. I just want you to understand how important it is that you accept yourself with ALL your "flaws". The other thing is that you love yourself. I know how clichéd it is and everyone nowadays seems to talk about it but really, it's probably because loving yourself is the first step in doing any "high aspiration" thing. Just try to treat yourself with the care and understanding you'd have with your own child. And I mean in practical ways. Like staring into your own eyes in the mirror every single day and saying I love you. Or like buying yourself presents. Just whatever it is you want another person to do for you. This is so simple yet so powerful and can lead to you not feeling the need for someone else's love so much. You are the only person in the world who can give you all the love you need. It's great if other people love you too but eventually, it's your own love and acceptance you need the most and I think that partly is what you are looking for in your obsessions over other people.
It'd be a good idea to just sit down and try to imagine you were not obsessing. How would your life be different? Would it be happier? or maybe empty and without any meaning? Also, try to notice when you get obsessive thoughts the most. Is it when you are stressed? When you are sad? Like for me it was when there was something stressful going on in my life. I didn't want to face it so I filled my head with obsessive thoughts to keep myself busy. Maybe you need to find a sense of purpose and obsessive thoughts give you that (because you know, the purpose is to get the person to love you), or maybe there’s something stressful in your life you don’t wanna face. It depends on the person I guess. Just noticing your thoughts without judging or blaming yourself goes a long way. It will give you a better understanding of what it is you need that you get out of this loop so then you can get your need met in a healthier way.
I remember I couldn't stand my own company those days I fell in love with guys that either used me (not that I didn't use them ) or just ignored me! It wasn't even imaginable to do things alone and actually enjoy them. Or just do nothing and not want to die! You seem to be much better than me in those days but still, I say just learn to have fun on your own. Have a cup of tea with you, plan a trip somewhere alone, read a favorite book, take a pleasurable walk alone, do whatever gives you joy and do it on your own. It's not like you have to enjoy all the time, the general thing is to just be alone and be comfortable with it but learning to enjoy is also a part of it. Enjoying your life alone (and I mean enjoying it like you couldn't possibly enjoy more!) and just being comfortable with being alone gives you the self-confidence you need in order to let go of the need for someone else's love. This need is contributing to your obsessions. I'm gonna share one of Leo's videos on how to deal with loneliness which might be helpful.
Meditation also helps a LOT. I have no idea why exactly but it's my personal experience that it has made me more aware of my own thoughts and led me to the magical conclusion that I don't make those obsessive thoughts occur. So it's useless to blame me. And perhaps it's a big step in dealing with obsessive thoughts. Leo has some videos on mediation and you have probably watched them but I'll share the one that helped me the most with you anyway.
Try not to demonize the ones you are obsessing about. You might not do it in the first place and that's great.But if you tend to do that, if you think they are "bad" because they don't pay enough attention to you or something, please realize this whole thing is all about who you are and not who they are. They might have their own problems but that's really not what you need to focus on.
All of this may take a long time and you probably will digress. You will have less obsessive thoughts for a while and then start to obsess again but this time they're just a bit easier to let go and this will happen again and again until you are completely free from the obsessions. Just remember to treat yourself with kindness and pat yourself on the back each time you make progress.
So, that's it I guess. Sorry for the long reply! I know what you feel. It's takes dedication to break free but believe me, once you do, you'll be much stronger and you'll have so much more self-confidence. There will also be more mental energy to spend on more fruitful and rewarding activities and this time you know how valuable this mental energy is because you can see the difference in the quality of your life when you spend your energy on say, enlightenment work and when you obsess on some guy. So look at it as an opportunity to grow.
Good luck to you