Boyfriend followed random girl on IG, claims it was a follow from a long time ago - is he lying?

Is it even possible? I tried sending her a request today and she accepted it in a few hours.
How can I know if he's honest? Some girls apparently take a long time to accept requests or are not so much active on IG even though she has over 500 followers, but for it to be over a year? He stoods by his "I didn't follow her while we were together".

He says he did have a desperate phase where he followed ANY girl just to pass the time when he was drunk, hearbroken or just looking, he claims he stopped that after some time and never had the need to follow new ones when we got together (we are together for a over a year) and also because he knows I don't respect it. We have been having a rough time lately and because of that he said he wouldn't do such a thing when we're like this together...

He said a classic line, that he isn't like that and that I can't even think of him liking someone like her...
He really keeps rehearsing the "it was a follow from the past".
And lastly when we argued he even cried a bit because we were on bad terms again. He told me he loves me and it's just his past, his past follows getting accepted... smh — Is that all fake?

She isn't really attractive, she's overweight too, but I guess any girl was good enough for him in his desperate phase? She's got 3 quite basic pictures there.

He unfollowed her after our argument without me asking him to do it and showed me convo with her (but who knows, maybe he deleted it).

It is hard to believe him. My guess is that I simply noticed she accepted his follow sooner than he did and thus he had no time prior to check her out except her profile pic.

Some time ago I did accuse him of a similar thing, but in the end it wasn't true. My mistake, but this is shady no?

I told him I don't wanna be in such a relationship, he said he isn't doing this anymore >.<

Boyfriend followed random girl on IG, claims it was a follow from a long time ago - is he lying?
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