Details are always good...
You sound way too inexperienced, nervous, shy, and unsure to be picking up bar *****s. You need to start with just getting comfortable talking to women. You're probably trying too hard, and they can sense it. You don't know what to say, how to escalate, or what to do. You run out of things to say, and don't know how to pick it back up, or keep her interested. You're giving off needy vibes, and they're giving you the cold shoulder. Bar *****s and hotties aren't going to help you with this. Some of them might even make fun of you, and make you feel even worse about it. *****es flock to the bar. They are shallow, mean, and have short attention spans. They don't care about talking - they just want to have fun.
You probably have a fear of rejection, and its holding you back. Don't let it. Get rid of it. Women are not special. Don't place them in a seperate category. They're normal human beings with flaws. It's not important that they like you. Just talk to them. Do NOT go in with any expectations, or get butt-hurt when you get rejected. Gotta toss the ego aside, and just get comfortable around them.
There's no need to be shy or nervous. Treat them the same way you do with your guy friends. Don't act all proper and polite. Don't worry in the back of your mind on if she likes you. Don't go out of your way for, or try to win her over. Just chill and conversate. Don't try to force a conversation, or think about what to say. Don't put any pressure on the situation. Don't talk TOO much, or hang around for too long. Just gotta chill and be laid back. Let the conversation flow naturally.
You are successful with guys because you don't care about what they think. You don't try to impress them. It's no big deal. There's no pressure. Your mindset changes with women - when it shouldn't. It's still not a big deal. You don't need them. When you think like this - it shows in your behaviors. You're not worried about seeking their approval, and that's when they come to you. "How come he's not trying to impress me? Why did he just walk away? Why won't he be my friend? Why doesn't he do things for me? Why doesn't he flirt with me? Am I not good enough?"
I'll give you an example of a needy guy... This guy, whenever he sees me, comes over to talk, and NEVER leaves. I talk for a few minutes about whatever, then I'm done. He talks and talks and talks. Stands right by me the whole time. I have to put the headphones on just to get him to leave. He does this every day... Never leaves me alone. Always wants to hang out, asks what I'm doing, comes into my house, joins me for every cigarette break.
If you're doing this with women - its very unattractive. Don't act like their shadow, or a creepy stalker. Don't hang around or talk too much. Don't be at their beck and call. Don't try to force yourself onto them. Don't stick around for longer than is necessary, or feel like you have to stay in their space and keep the conversation going. Don't make it awkward. Don't go ape**** whenever a hot girl talks talks to you or shows interest. Make your rounds. Talk to lots of girls, and people in general. Become sociable, and make a group of friends. Expand your social circle. Don't act needy, and success will follow. People pick up on your vibes - whether you realise it or not. You might not even know you're acting this way, but you are.
It must be repeated: treat women like you do with guys. You don't always talk to guys, or respond right away, or do favors for them. You're cool to chill with. Be the same way around women. Don't always be available, make them your #1 priority, or try to force anything. No expectations. Just have fun.