<human>: My girlfriend (Nikki) had a previous relationship with (Tom) for 5 years; although she says the last few were just going through the motions... long story short, she was friends with Tom long before dating, so now almost 4 years into OUR relationship, she wants to see him occasionally. I've gotten pissed before about it (and never really trusted the guy based on what Nikki has told me), but let it slide... Tom currently has a girlfriend of his own... all good so far, right?

So, Nikki comes home last night after hanging out with Tom and his gf and tells me that he's still kind of the asshole he always was but glad she got out to see them... Then at 1am her phone starts receiving texts but we both sleep through it.

As a guy, I know how guys think and I've never really trusted Tom (although I DO trust Nikki)... I did the morally questionable thing this morning and checked the texts - all from him saying how he misses her and she's only with me because she "just got comfortable" and she should "jump out and take a chance." I didn't tell her I saw anything, but asked her if she's sure Tom has no interest in her; she denied completely.

So, what do? My initial thought is to lay down the law here - I hate ultimatums but I don't see any way around putting a dead stop to this guy's bullshit; if he's truly a "platonic friend" he should be looking out for her best interests; not trying to fuck up her relationship... And now she knows for sure what his intentions are and she's lying to me about them (maybe to save face?); there's no excuse to lead him on - I have no idea what is going through her head. 

Do I come out about reading the drunk texts? Do I jump ship myself? Tell her to pick one of two phone numbers to delete out of her phone?

Can you condense the text into a few key points?
<bot>: Girlfriend went out with her ex and his new girlfriend last night; he professes his love for her via drunk text; she denies it to me.