hi just thought i needed to put down in writing how i have found my wife to be a cheating slut that she is. it all happened a few days ago but i will say that for the last couple of years things haven't been too exciting in the bedroom hence i have discovered my bi side for some action but that's another story. Over the last few weeks/months i have noticed that whenever i mention anything sarcastic about our sex life i get a response that is not forthcoming and proves that i think the spark may have gone. Anyway i decided to make a few investigations regards her workmates etc and there are a couple of guys i know who work at the same place but in different departments but they told me that on a couple of occasions my wife has flirted when out on an office get together. there was such a get together planned and she informed me that she was going along and requested if i would give her and another girl Sarah a lift which i agreed to. I duly dropped them off and she gave me a peck on the cheek and i said "be good and if not be careful" which she just gave me a wry smile and that was it. Unbeknown to her i was to return to this pub later as i thought i could catch her up to no good. I arrived and the pub had got real busy now as it was late on which made it better for me to mingle in a crowd and watch from a distance. I set myself up in a small alcove and watched patiently as she was chatting and giggling like a schoolgirl with some of the lads who i presumed were from the office. One in particular who i have since found out is called Gary was showing her added attention by getting in close and i could see him placing a hand on her thigh and buttock and she was giving no resistance. I watched them talking closer and closer and had sort of divided from the pack and i saw them slope off towards a rear door of the pub which led to the large car park. I slipped out the other door and quickly went around the building to the rear but when i got there i couldn't see either of them. I was about to return to the inside when i heard a giggle which i recognised straight away that it was Debra my wife. Right i thought i will show you and walked over to the bush covered area at the far end of the car park but when i got there i first of all peered through the trees and saw them both together. I don't know what made me stop but i did and i watched quietly as i saw my wife and Gary kissing and feeling each other up and to say i was getting hard doing this was an understatement. A few minutes passed and Gary lifted Debs top up and removed one of her breasts from her bra cup and began sucking on it and she began to softly moan. she was reaching now for his trouser belt and began to undo it and release his cock from his pants and began to wank him. He pulled off her tit and had hold of her head and slowly pushed her down so that she could take his cock in her mouth which she duly did and he began to fuck her mouth. He started slowly but then got a bit rougher as he progressed and Debra was gagging a little. Now she doesn't and hasn't apart from one time early in our relationship take cum in her mouth but what i witnessed next shocked me. Gary held her head strongly and firmly in one position and push his cock in as far as he could and obviously was about to shoot his load. Debra attempted to pull back but he held her so tight she couldn't and he pumped his cum into her mouth. She was there with eyes wide open and had no choice but to swallow every last drop and then he pulled away from her and just pulled up his trousers and suggested that they went back inside which was my Que to leave and i hastily retreated back and skulked back to the pub. Once they were back inside its like he just ignored Debra and was chatting to his mates again and she seemed a little dejected and at that she got her phone out and then i felt my phone vibrate in my pocket and i went outside to answer and she asked me if i would pick her up as she was ready to come home. I went back to my car which i had parked away from the pub and then collected her and when she got in i asked her if she had a good time and she just replied "yes thanks but a bit boring really". Oh if only she knew that i had seen her basically be used like a slut. Not sure how i should handle this though!