I've been talking to this girl for 1.5 years as fwb, soft nexted over the summer to avoid long distance

She's been in pursuit of a LTR since we re initiated contact post summer and has been getting close to it so I laid down boundaries that if it was something she really wanted she shouldn't be hanging out with her friend group at her Ex's place he shouldn't be in her life. She never goes over there unless all her friends go but even still it makes me uncomfortable.

She went silent tonight over text so I checked her location on snap maps and she's there. She came over after and I asked what she did and she omitted the fact that she was there.

How to proceed? I haven't confronted her that I know she went there