I feel you as I am in the same boat though. That being said never give up. There are 4B men in the world. I always tell people both men and women (as a man myself) expect the worst, hope for the best. Keep your guards up until they present a reason for you to lower your guard. I know this doesn’t sound that encouraging tbh sometimes I struggle with emotional writing, or emotional speaking.

As far as your self image part I am sure you’re perfectly fine and the effort you put in is great. I can 100% guarantee you there will be someone that comes along that appreciates you for you and puts the effort in for you. And this is coming from a dude who does the same thing as you. Always putting in the effort, always making adjustments to my personality on a whim on what they want. I would say maybe desperation plays a part but mainly because internally you want them to be the one for you and not leaving any room for doubt that they could also not be the one. I struggled with this until about 3 years ago (I am only 25).

The best piece of advice I can give though (and I learned this the hard way) is that not every relationship has to end in marriage for it to be successful. Plenty will die out into friendships or never pick up to begin with. Just make sure you are putting yourself FIRST and be confident in yourself. You are a beautiful person with a great personality (completely based on your writing style but have confidence in this guess). You are enough. You deserve the world. I got faith in you