I don't know what happened with a girl I know. She used to show a ton of signs of interest towards me and I was going to ask her out. But the past couple weeks she's basically been ignoring me. And now she's showing signs of interest towards a friend of mine. Whenever I'm walking in a group with her she never even looks at me anymore. She'll talk to me if I talk to her but she never brings any convos up.

And just a month ago she was always bringing up convos with me and always showing signs of interest and giggling at things I said.

The only thing I can think of is a couple weeks ago I started to show interest in her.

Should I still ask her on a date or have I lost her to my friend?

You haven't lost yet, but you're cutting it close. Strike up a conversation with her, throw in some Kino, and see what happens. Best of luck to you.

she is ignoring you because she is upset you didnt ask her out yet.

gotta get while the gettin is good, ya know.

I'm in a very similar situation right now (except for the friend part). The girl "changed" once I showed interest. For this aspect of it, I cannot help you - perhaps others can.

But I will try to help you out on another part, since there is another "competitor' looming in the shadows (your friend). In this case, you must take action - interact with the girl (flirt/kind/convo/etc.) and hopefully, it works out.

Pretty much what ThisGuy said.

Hmmm... i see a pattern here:

Guy shows interest, girls starts ignoring guy.

Trying laying back a bit. If she keeps ignoring you, you ignore her back and talk to other girls.

If she's ignoring you, then giving her kino & extra attention is only going to make things worse.
Thats what nice guys do. They supplicate.

Penkitten is right, you shoulda asked her out when the getting was good.
I don't think there's much you can do now, and this last ditch effort to "get the girl" seems kind of desperate to me.

The only thing i can see working out in your favor, is if you become more sociable with her other friends and make yourself the center of attention.
She'll get jelous, and ditch your boring friend.

It's all about social hierarchy, out-game his ass.