Love is staying together when things get boring and difficult. Love is coming out of the re-negotiation period that happens after the excitement and lust, in tact and closer. Love causes you to have to make sacrifices.
Being able to grow with someone and develop a truly loving relationship takes knowing yourself, and wanting your life to improve. If you dont want to face the challenge of becoming a better and more rounded adult, it wont work.
The biggest step i made was realising you cant have it all, in anything in life. You have to commit to something. You wont find happiness moving around taking small chunks from everything. Choose one girl, with her flaws, give her the best relationship shes had. Choose a career path and stick to it, be the best at it. Care for your car, get it serviced. Dont give up on hobbies that offer constant development. Dont put time in to things that make your life worse.
I used to get bored and leave, or see arguments as a problem. I had to realise that you get bored of anything in life, no matter how beautiful, exciting or costly it is. And that arguments and digs are just ways of your partner doing their best to make the relationship work, and sometimes even the hurtful or irrational stuff has its purpose. Some people need someone who is stronger than them, so they will test you, the theory being: "if they cant take me pushing them a little, how will they cope with the world and protect our potential family". But you have to be careful that doesnt turn in to abuse. Another topic though.
The point being, the hard, boring, and sometimes upsetting stuff, isnt the end. Its what builds proper love between people.
That doesnt mean you cant have the opposite in equal measure. Growing really close to someone can bring lust that youd never have from a stranger or new partner. You can have more meaningful experiences in general. You can enjoy new things and share old memories. You can build eachother up and do more than you thought with each others support.
And buy your partner random nice shit.
If you havent had the experiences you want, if youre gonna feel regret for not doing certain things, then get them out of the way. Dont get in relationships for sex. Dont get in relationships because youre lonely. Get in one when you dont need anyone.
I have attachments and pain from leaving partners i wasnt ready to love. It wont go away. Its definitely damaged me emotionally, and i feel guilt for leaving good partners.
Tldr; its boring, but that brings excitement and growth. Stick at it for your sake.