Me and my girlfriend of 6 months are going through a bit of a rough patch, as of late I've begun to distrust her. She lied to me about something and since then I've felt weird, lately i have this weird feeling like maybe she might be wanting to rekindle her relationship with her ex. I feel weird and I've become distant but she doesn't really ask why I'm distant at all. Should I talk to her about it or just distance myself and wait for her to ask?
i would talk to her. Being distant and hoping she'll notice isn't going to solve any problems. If anything, it will create more. It's possible something is going on with her and she doesn't know if it's okay to talk to you about it since you've been distant. Perhaps reaching out and talking to her about how you feel will help you both understand each other better.
I know it's scary and hard to tell someone how you feel. But sometimes it's necessary. Especially if you want to keep the relationship going.
What makes you think she is thinking about rekindling things with her ex?
Well, I can understand that she lied to you and because of that you are unable to trust her like before. Yes lying does break trust and to add to that she not asking you why you are being distant is also not a good sign, I can understand that will make you doubt even more if she indeed wants to rekindle her relationship with her ex, your doubts are valid. I understand.
Yes, you should tell your girlfriend how weird you are feeling. Be honest and open. Communication is very important in relationships.
No no no relationships are about communication! Trust can only come if you communicate. :) Talk to her. Obviously don't accuse her, just tell her that you're worried and that you want to talk and fix things. :) Otherwise this thing between you will just keep getting worse and worse and you'll probably end up losing each other. If you like her, go talk. :)