GF [F] of 5 years just let a guy cum on a certain area. Left me [M] with disbelief. (Part 1)

So to explain the situation, I am together with my gf since about 5 Years. I am 25 and shes 23. I work in a big company as well does she, but recently she got the chance to promote to a high position. Only bad thing about it is that she has to work 120kilometers away from our home. We talked trough this and decided that she has to take the opportunity since she can get back in about 3 years keeping the higher position. So we looked around and found a shared flat there which was ok for us price wise and the guys seemed to be nice.

About my gf, she is a very enthusatic 5.4“ girl with long blonde hair. She does a lot of sport so she got a very trained body with a nice bubble butt and B to C Cup sized Breasts.
We are very alike characterwise which is why we match that great. But she always is very flirty with guys and doesn‘t care if guys get all touchy since they don‘t mean it that way in her perceptions, you could call her naive. She also always tells me every little detail if something happens.

Nethertheless fast forward to this week she told me about some of the habbits of her new roommates. They usually only wear underwear at home. One guy is a broker ans is barely there. the other guy is a semi professional hockey player who is there most of the time.

They have only one dining table in the kitchen which is already really small and only has a cornered bank to sit on. she also told me that everytime she wants to eat on the table the guys are already there sitting on the edge of the bank so she has to kind of rob over their lap to get a seat but she doesn‘t mind as they told her that they always sit like that.

So this morning my gf got up and was wearing her pijama (a short shorts and a cropped top) which i know for a fact is the only thing she wears for sleep as she doesn‘t like wearing a bra or pantys at home. She then told me she needed to confess me something.

As she went to sit on the table, she robbes again over the lap of her roommate (the hockey player) to breakfast on the table. But this time she could feel a bulge while passing his crotch and saw that he was errect right after.
As i already said she is very flirty so she started joking around with him complimenting him for his (her words) huge dick and he made her guess his size, apperently 21 cm. ( i could not say a word while she told me that on the phone). She told me they went on talking about sex positions they liked, what made them horny and my gf told him that if somebody tickels her she gets all wet and she gets peak horny if someone is touching her nipples. He then slipped his boxer up a bit revealing his dick asking her for a ride but she told him that she is forgiven and wont do something like this.

What then happened shocked me and made me tear up in disbelive.
She told me that she sorry but she wanted to feel his bulge rushing over her gential area again and even though the other roommate left after they startet talking about his dick, she again climbed unnecessarily over her roommate facing him with his errect dick out of his boxers pressing against her shorts. While she was on his lap he screamed „tickle attack“ and startet tickeling her so she could not move but she told me should could feel his dick pressing against her vagina in her pijama pants. His tickels were on her waist and under her arms but sometimes rushed over her nippels (her weak point) and even grabbed below her shirt switching and twitching them. the movement forced her to rub her with little fabric covered vagina right on his tip of his dick the whole time. The mixture of his precum and her wetness made it hard for her to stop it and she was so horny at that moment.
She also told me that what then happened then was totally not how she behaves usually and will never let that happen again. So her pants slipped aside from the movements he made and she felt his bare tip was rushing on her labia up to reach her clitoris easily as his precum added to her wetness. He then pushed her up so he could slid all the way to the entrance of her vagina where she had to move downwards so in all wetness his dick would not slip in. She said that it was hard to prevent it with all the wetness and precum and a few times the tip of his dick slipped a bit into her while she was fighting to get it out yet again. She told me this went on for quite a while like 10-15 minutes and then she could feel at one of the bare strokes that his dick startet twitching then he fought to push his dick as far inside of her as he could and warm ropes of cum then shootet direcly into her (she said it was only the tip but it was very noticeable as he has a huge dick) while he was still cumming she slipped his dick out of her but that made him also shoot against her pussy running down on her labia. He then slipped it down again and he then managed with all the cum as lube to easily push himself completely inside of her as his last ropes shot into her once again. She said that this pushed her over the edge as his 21cm were to much for her and she came on his dick while he playing with her nippels.
After a few seconds of his dick resting inside of her she said that she had to get ready for work and made clear movements to stand up. He helped her to pull his long dick out. She now saw what they did … she left a huge wetspot on his grey boxers his dick was all out and creamed by her vagina and a lot of cum. She then looked down on her short grey pants which were totally soaked with both her wetness but mostly covered in his cum (he apparently shoots a lot of cum). She felt that it also was running down on her inner thights and she told me that she could feel the cum all over her labia and clitoris as well as inside of her. He said that she should continue but this time riding on his dick, but she made clear that this was one time only and an accident. She then went to her room and called me directly while still soaked in his cum.
She appologiesed a dozend times to me and said „ i know that this sound so wrong but it was nothing even though he came direcly on and in my you know… Don‘t be to upset honey it was only fun and things like that happen in such situation, i have to go to work now as I am late already. Don‘t be mad but i have no time for a shower, i will just whipe away the most and leave the rest hoping that it does not leak to much at work. Love you bye.“

Before i could say a word she eventually hung up.

I am shaking right know and don‘t what to do.
I love her and need her in my live but this is to much for me…

Source: reddit.com/r/gonewildstories/comments/t9v9qm/gf_f_of_5_years_just_let_a_guy_cum_on_a_certain