I'm sure most of us can relate to this: in order to be relatively "stable" and not exacerbate the worst of our BPD symptoms, I've found that the only thing that works best for me is to keep people at arm's length and not pursue very deep relationships. ESPECIALLY romantic.   
I've made it a personal rule to refrain from developing romantic feelings for anyone, not get too attached to anyone, because as hard as I try to be "normal" I've not been able to maintain peace. I slip up and ruin everything.   
I had a crush on this girl for 5+ years and we weren't even acquaintances, we had similar interests and fandoms and mutuals on social media at times. A relationship she was in had just ended around the time we started following each other. I really felt like I could relate with her, like I said we enjoyed the same things, we agreed on so much, and she is so beautiful and funny. Me falling hard for her was inevitable, but I never acted on it. I didn't even know how to approach as a friend because I knew I'd be too much, so I just kept my distance. She was already going through a very difficult breakup and I vehemently did not want to be just another problem for her. I really want the best for her.  
And there were times where I took a break from social media for my mental health, and I come back and she is already with someone new and they're madly in love. I put my feelings to rest, I knew I had an even lesser chance. But it was okay, because she seemed to be at her happiest. And in the end, I did pray for that for her.   
But fast forward to now, they've been broken up. She had another new relationship and it soon ended. I've been in a relationship myself in between all this time, but it was abusive and I was unceremoniously dumped. I don't know what possessed me to reach out now of all times. Someone close to me had died recently and I had a revelation like, "now or never. Don't wait to tell someone that you love them. Let people know you care about them while you both exist on this crazy rock."  
That was my mindset anyway. I didn't confess my feelings RIGHT AWAY. But I just finally started properly talking and stuff, but it unfortunately awoke all these deep feelings of infatuation that had been lying dormant. These feelings just came forth like a storm. I fell even more in love. She was so kind. It may have been impulsive, but I really had been trying to hold it in. Especially throughout all these years. I thought, since I tend to have the illusion of mental stability during these periods of time when I'm basically a lone wolf (with no close attachments than family and some friendly acquaintances with coworkers), I thought maybe I could handle it and not lose my head.  
I was wrong lmao.  
So, I confessed. Spilled my heart out. Reassured her that I just wanted her to know and didn't expect anything. She was very kind and even said she was kinda developing a crush on me. That blew me away. I became way too happy. Every notification from her, I was extremely happy.  
But she became distant. She didn't seem as interested in talking to me like she used to. She would be online and talking to others, but took more than a day to respond to me and I tried to give her space. But it hurt when she never initiated any conversation. But I held back because I seemed annoying always being the one to talk or put effort.  
She stopped inviting me when she used to invite me to things at first. I may have been quiet during social gatherings, but I was always grateful and was happy to hang out with everyone. I'm just shy at first with new people.   
I tried giving a gift since she gave me a gift before and it was very sweet, but acted weird about it. I just wanted to give something that made me think of her and said hi, didn't stay long because I knew she was busy. She had other friends over. She said I was always welcome and I believed that. I slipped up, it wasn't the right move apparently. I realize that now. (Note: This is all on a virtual setting btw, on a certain MMO)  
I tried to confront her about it, just tried to tell her how I felt ignored. She said she liked honesty and wanted me to tell her if something was wrong. They always say that lol. And she said she didn't want to always worry about how she was making me feel. She said I was clingy. Off-putting. These words felt like knives. :) But it is to be expected. I mean, this is so classic, isn't it.   
I split. Because of course I did. I didn't want to cause her any more issues. I explained as much. That's a step up, because usually I would have ghosted silently in the past. As awful as I am, I felt I owed her that at least. It just hurts too much to have a one-sided crush and be an afterthought.  
This is why I take YEARS to even try to pursue anything, because the damage is so much and it doesn't feel worth it. I feel much better not having romantic feelings.