I can’t keep doing this anymore

30M here, today I asked out my crush at work and got rejected. I’ve never been able to pull any of the girls I liked ever. I’ve never had a relationship just 3 situationships and none of them lasted long or well. I’ve had a crush on this girl at my job since I started working here. Our company is going out of business soon and my supervisor encouraged me to shoot my shot with her. For the past 3 months I’ve just been talking to her making small talk asking her questions about herself, really showing interest in her and trying to make her feel comfortable around me. I initially didn’t want to try with her because I just already knew she wouldn’t like me but my supervisor encouraged me, as I never know what could happen. I wasn’t being pessimistic i was just being realistic. Im just not the kind of guy who girls line up to want to date. Today I finally asked her out, I know I took her by surprise, but she told me she wasn’t available to be dating. And no shade to her I’m not knocking her she has every right to decline me this post isn’t to shit on her or anything like that. The fact of the matter is that I’m 30 and I’ve never had a girlfriend before and it seems like more than likely I will never find anyone. I’ve already missed out on young love or even being someone’s first love. And before you say I need to put myself out there or get hobbies, I go to the gym, go to conventions, work on my car and I have lots of friends. My social life is pretty fulfilling I think. I’m on dating apps (i barely get any matches and the ones I do match with never respond) and I don’t have a problem speaking to random strangers I do it all the time at bars. I guess this post is more of a vent than anything else. But yea, starting to realize nobody exists on purpose, nobody belongs anywhere and there isn’t someone for everyone. I just feel like no matter how hard I try, I can do everything right and I still won’t find anyone. I’m more likely to die than to ever be able to say I’ve been in a real exclusive relationship before.