ADHD, bandwagons and being easily influenced?

Still trying to understand my now ex's  'ways' so I hope you don't mind another question.

It always seemed to me that my ex never had an original thought of his own, he always seemed to be heavily influenced by others, or whatever bandwagon was passing at the time he could jump aboard onto.

Everything from small trivial everyday stuff right up to big stuff like wanting to emigrate because a work mate moved.

He would often throw his hat into the 'wrong' ring and end up soaking up whatever someone else said and if that someone wasn't the most balanced of people then he'd end up being led down a bad path. As an example - he gave up a good job because of this very situation. He soaked up everything that a particular (very negative) work mate said and jumped onboard his complaining bandwagon with little thought

He wasn't happy with his job to start with but to be fair, he's been like this about every job he's ever had. However, he just emotionally reacted to the work mate's complaining and before we knew it, he had built up an emotional picture in his head about how awful his job and his employer really were and he quit.  He very much regretted it as soon as he had done it and tried to get his job back but it was too late. He admitted he had been foolish and he shouldn't have got so caught up with other people's thoughts but he hasn't learned from it and continues to do the same thing.

I've just recently become aware of just how influenced he has been by a work mate about our relationship / breakup. He has been coming out with stuff (about me / money / what should happen now etc) that I know he would never have come up with on his own and tbh I think this person has swayed him more than he knows. The work mate doesn't know anything about me or our family or our finances yet that hasn't stopped him from voicing his opinion about what my ex should do.

I can't help but feel if he had got into conversation with a more balanced person then perhaps he would have been influenced lin a less negative way and we could have worked through some of our issues.

I realise it's all water under the bridge now but my non ADHD logical mind needs to go through a process of understanding before I am able to deal with it and move on.

So, does any one recognise this tendency in themselves or their spouse? If so, were you / they able to recognise this was a 'thing' and could you / did you change it? 

Once you were influenced / convinced of something, were you able to do a 'U-turn' and be able to change your thoughts or were they too fixed by then?

I would still even now, love for him to agree to see a counsellor with me but he wont as he says he doesn't love me so there is no point. I believe love is a fluid emotion, it can ebb and flow like the tide and in long term relationships it can feel as if it's gone even although it may just be overwhelmed by life's crappy times.

On the other hand, he believes you shouldn't have to work hard at relationships, if you need to work hard then they aren't right to start with. He just wants the fun happy stuff.

Anyway, back to the question..........