There's a fact-checking site here:
https://fullfact.org/europe/eu-facts-behind-claims-uk-influence/ that discusses the matter reasonably impartially.
As the site points out, each of the times the UK was outvoted was most likely very important to some people - even though the majority of the UK population probably didn't care (or even know) about the vote.
The reason the majority of UK voters were unhappy with the EU (IMO) is not so much to do with the UK being outvoted in the EU on a few occasions - rather it was the creeping loss of control to the EU. The UK governments of whatever flavour at the time may well have voted in favour of some measures, but that doesn't mean that their decisions were supported by a majority of UK voters.