Should i stay or should i go......?

Ive been with my bloke for 5 yrs, (its just occurred to me neither of us rememberd or made an issue of our anniversary date -unusual for me) anyway we dont go out 2gether much coz we find gettin a babysitter awkward, we have 2toddlers. Wenever Ive been out or he has a drink, I sometimes get the cheatin talk- have I ever, if I ever, he knows I have, it gets to the point of arguin and I just walk away coz I NEVER have. If I go out with girlfriends I get texts sayin stuff like dont run off with a bloke. Sometimes I get accused of it to an extent where I feel like hes tryin to cover his own cheatin, its always popped out of the blu & he always starts it. Anyway lastnite we went out with friends. Ther was a woman in the bar who was chattin up both boys, I thought nothin of it, then my guy grew distant, everytime the boys went to the bar or a smoke ther she was. One point they were takin ages havin a smoke so I went out for 1. As I walked out my guy friend alerted my fella who looked up like a scared rabbit in the headlites, they were both talkin to her, I was a bit alarmed but shrugged it off, my fella went in & I was left with my friend & I asked if my fella was chattin her up to which he said no he was, Ive known my friend for years & think I can tell when hes fibbin! I think he was. As I walked over to lite a ciggie I saw my partner very close to a lady & he was whisperin holdin on her arm she kinda tried to pull away & not really pay attention but he was doin it in a way as if he was a drunkard chattin her up. I fronted him about it & he laughed said was just talkin to & Im mad, I said he was actin other wise & after a bit of banter it seemed it was effort for him to kiss me. The nite went on normally,once home he didnt seem to wanna touch me, nor in the mornin, I got a quick cuddle & a kiss on cheek, now my thoughts are racing & im quite upset, did he do somethin? Does he cheat? I couldn't stand it if he did, but if I left id have nothin & my kids be heartbroken.