So lately my (33m) girlfriend (32f) (we have been together almost two years—living together just over 6mo) has been acting very weird and possessive of her phone. All only in the past two to three weeks

I notice she swipes away from things on her phone whenever I walk close by or sit next to her. This never used to happen in our relationship (though I will admit, 2mo into living together, we had a pretty big talk about how I feel like she’s always on her phone and not engaging with US as much as I feel like we should) I want to chalk this up to having had that talk and her trying to be respectful of our close time, but I can’t shake some thing.

I’m worried that she’s used an old work friend as an excuse to meet someone else.

Every time I ask her about it, she responds weirdly. She says she’ll message “message [friend] about it now,” but she never does while I’m near her, though she does dozens of other things on her phone in the meantime. She almost seems reluctant to let me in on the details or even confirm them after she mentioned it last Thursday as a possibility. My spider senses are going way off at this.

My rational mind would like to think this isn’t what it seems like. I have to at least trust that this isn’t a worst case scenario, but I know something is off and it feels like I’m being lied to, however innocuous it might be.

Would I be the asshole if I followed her to her plans with her work friend to prove or disprove my suspicions? I do not want to resort to going through her phone to find the answer. I find that to be ugly, uncouth, and a slippery slope.

Addendum: It’s not that I trust her so little. I don’t want that to be lost in this. Maybe I didn’t make this point well enough.

No, I do not think she’s cheating. I think she’s up to something she perceives I would be upset with and is choosing to be dishonest about it.

I think people make assumptions that doing things to confirm your feelings always results in “the end of a thing.”

She’s been through my phone before found nothing and came clean about it. And I appreciate that more than anything else as far as that situation goes. So I think there are ways in which it’s acceptable to find things out. Just don’t think that going through the phone is one of them.

EDIT: I think the best way to go about this is to straight up bring my concerns to her. The bottom line is I don’t feel like it’s cheating going on and I do feel like if I present it in a meaningful way, it will be met with the honesty I am looking for.