did i handle this correctly?

ok so im going to appologies already for the wall of text.

i've been with this girl who is 26 years old has 2 kids, i am 22 years old. we been together for 8 awesome months with no problems until these past few days. I go up to visit her on my days off from work every other week, 4 hour drive between.

this past time i went up, and everything seemed normal. until i started noticing her acting a little wierd, i asked her whats up why is she acting this way. she said its nothing. then i started noticing things, acting wierd and a tiny bit distant, on the phone texting alot. didnt think anything of it really was just a little confused, called up my bestfriend and asked him when he cheating on his girlfriend what was some of the signs she started seeing, he began naming them, and further he goes down the list the more im checking off in my head. now im on her computer, and he phone is infront of me, she making dinner for the kids at this point. i tell him im seeing alot of those signs, and ask him should i look? he says if you really worried about it, it cant hurt. what do i find but all measages erased in the phone, sent, recieved, drafts everything gone. at this point im going omg..omg. but my friend tells me to calm down and wait, wait for more signs.

so i do, the next night same situation, he phone is infront of me and shes on the sofa, she recieves a text from a friend who is a boy, she says they been friends for 10 years and hes nothing to worry about, so i never thought of him possing a threat. so i pick up the phone and throw it to her saying "text from jason here you go" i dont look at the msg i just throw the phone. she immedietly goes quite and begins texting. this friend of hers is best friends with her ex-boyfriend. it gets pretty wierd, i asked her hey wants he up to? and she says "he is trying to convince me to come over and hangout, i never do tho" but even after she said that to me she kept texting, now im sitting 5 feet away from her. rest of the night my mind is racing, later asks me if i wanted go to a resturant with her friend(different friend her bestfriend) hang out for a bit and everything instantly turns back to normal. at this point its eating away at me. we finish dinner and drop her friend off, we go back and go to bed after watching a movie, i didnt sleep at all, i was up all night, i couldnt stop thinking. those measages could say anything.

so the following morning finally after the kids were dropped off and it was just me and her left in the house, at this point she is taking nap, we got back really late. i broke down and finally just looked at the measages. they read "hey come over me and EX-BOYFRIEND(not gonna say name) are here hanging out" "EX-BF wants you fantastic boobs in his face" and it goes on from there, she doesnt say anything like "stop, or f**k off, or even mention im 5 feet from her" she just kept texting him. then i read "come on and just hang out with us, you gotta be getting sick me sexually harrassing you for the past 2 week" and the control switch in my head just flipped off, i stopped thinking, i couldnt breath. ive never had to handle a situation like this.

i sit her down and confronted her about it, starting with "do i treat you right?" and came out with i was snooping because she was acting wierd, she says its just him being drunk and he doesnt know what hes saying. i asked then why did you disrespect me and still engage in the inapprorate conversation when you have a boyfriend, why would you talk to him when im 5 feet from you and say he just wants you to come over, when its so much more then that. you didnt tell him to stop you, you basicly went along with it. she understood why i was snooping and why i got upset, if she just told me when she got the msg that he is playing matchmaker for ex-bf, i wouldnt be in the situation, i can handle it better. she said sorry and she will do anything to get my forgiveness, she even offered to stop talking to him, delete him from her life as best she could, and i said i dont want you to do taht, but if hes going to play matchmaker if she will do that for me? she said yes and immediately hands me the phone, she tells me to delete everything from him, i delete msgs, his contact and his number. i then ask why she didnt tell me taht this has been going on for 2 weeks, she said she didnt think anything of it, and she doesnt want to upset me. i asked her if she went along with this for 2 weeks she must of like the attention, and she said no, then i asked why didnt you tell him to stop and she said she tried a few times. i then said "it didn't click in your head thats its inapprorate to do that especially when im sitting right there and if this has been going on for this long you should of told me if you told him to stop a bunch of time. now she was crying the phone time, so after i was done talking i calmed her down and got a sm