Weird friend?

So I met this girl on FB a couple years ago, and we’ll call her Liz. Liz and I started liking each other’s pics and eventually started messaging. She added me on snap and we got pretty close and talked every day. Eventually she came to the mall where I worked at the time and brought me cookies and food here and there.

I was talking to this guy named Dean, and I was really into him. She didn’t like him and kept telling me to not get too attached and he’s a bad guy, he ended up being an asshole (after we stopped talking) so maybe she was right, idk. But even besides Dean, she didn’t like anyone I talked to, she called everyone I talked to ugly.

But randomly all of a sudden, she deleted me on Snapchat. I didn’t even notice because we didn’t get in an argument or anything. I texted her and said “um did you delete me on snap?” And she said “yeah lol long time ago” like what?? And I sent her a confused gif and she didn’t reply for 6 months, I deleted her off everything since I found that really odd, then she randomly texted me this morning saying “aye hoe”

I told my sister who I’ve told about this whole thing and she says something is wrong with her/she’s crazy/to stay away from her. What do you think?