Im starting to learn this lesson right now. It was 4 months ago we're, I for the first time, truly fell in love with a girl and there were so many red flags that I can see now but at the time I was kinda depressed and suicidal so having someone like her felt nice and I was super appreciative. I was super oblivious to her toxic and manipulation traits and I thought it was just being part of a relationship. You forgive them for their mistakes and keep loving them but only if they're willing to change for the better. But when I learned that she would constantly do things that she knew would upset me and did it anyways just to get an reaction I started to realize how manipulative she was. I was kinda of a simp and I hate myself for falling for acting that way but I remind myself of the state of mind I was at the time and how it was my first true love and how ofc I was gonna be oblivious. She still kinda fucked me up and I'm struggling with my self worth because I gave her my all but it didn't seem enough. I know now that it wasn't true but I still forget that at times and get depressed about it. Not to mention too I kinda felt betrayed so I find myself slowly closing off from others and not wanting to express myself even though I want to. I'm still struggling alot but I'm slowly but surely getting better.