I have been with my girlfriend for five and a half years. we've lived together for over four years. our relationship has always been strong and we get on great. Gradually over the last two years our sex life has faded a bit. She now has a very low sex drive. I have never pestered her about it. I am patient. I have learned to deal with it. That's fine.
Three months ago she started a new job and started to go on nights out with her new colleagues at least once a week. I have no problem with that at all.
Now, comes the trouble. About two months ago she went for a night out after work on a friday. There was nothing unusual about that. She came home a little later than normal, was a little drunker than normal. I was in bed asleep when she came home, but she woke me up when she got into bed. She was out cold within in a few minutes - I was sober and couldnt get back to sleep. I got up and went to the toilet, and found she'd undressed in there and her clothes were all over the floor (nothing unusual about that either). I decided to pick the clothes up and bring them to the laundry basket. When i picked up her panties, i found them to be damp. I dont normally check my gf underwear but felt compelled to do it on this occasion.
I found what looked to be a fairly fresh cum stain. I was obviously a bit shocked, but i didn't hit the roof and said nothing to her about it. I realise that women have vaginal discharge and felt it could be that. But i had to be sure.
I am not proud of this, but i decided i would secretly check her panties (you may think this ridiculous but put yourself in my shoes for a moment). After about a month, i saw a clear pattern: her panties are clean right throughout the month, every day the same. Yet, the panties she wears on nights out almost always have a white/silver stain in them. And then i found a black blouse she'd worn on a night out - in the bin. It had a similar stain on the front end.
The strange thing about this is: for the last two months she has been her old self. She is more loving towards me, takes more interest in all the things i like, wants to spend more time with me, and we are talking to eachother in the same way we did in our first year together. And our sex life has returned to what it once was.
What the hell do i do??
I think it's obvious she is having an affair. But at the same time our relationship has improved ten fold...