"So can anyone honestly say they have ended a long term relationship as soon as they had a gut feeling their partner was doing something that was a deal breaker to them?"
Summary: it’s much harder than lots of posters think to end any relationship based on suspicion alone. If you are an honest person who encounters a partner who seems to obfuscate, but provides reassurance, you want to believe the best in them. It messes with your head. Especially if your only prior experience is trustworthy family and friends who are open with you. It’s unbelievable that some- one you love can be so sly.
Backstory: I ended a relationship after a year of magical dating, based on a gut instinct. I then very foolishly accepted his explanations and remorse and got back together with him, accepting his contrition.
Longer story: in summary on my very first date with a divorcee, I asked him why his first marriage ended and if he’d ever been unfaithful. He looked into my eyes and said “ categorically not”.
Fast forward after a year of magical dating, during a drunken romantic dinner, I asked if there was anything else about him I should know? He admitted that he’ d not mentioned a relationship with a married former work colleague “ Sarah” which had ended before he met me. He said it only started after he had left his wife. He said he and Sarah had provided mutual support about their unhappy marriages for months , and that he had an affair with her, after he had left his wife.
My gut said this was a dealbreaker as (1) he had misled me for a year about his marriage breakdown and (2) he had been happy having a shabby sneaky affair with Sarah, who remained married.
What I did initially was what I’d always thought I’d do: I ended the relationship that night - he had clearly misled me by omission since the very start of our relationship.
For a fortnight he begged me to reconsider, said it was different now he’d met me. Said I had to forgive one mistake as he had now been honest etc etc.
What I then did: I very stupidly forgave him. (1) he had now told the truth(2) he showed remorse (3) he convinced me it would never happen again.
Of course, that was the start of a 15 year troubled marriage - we’d have a good few months then an episode would happen with things that didn’t add up ( mostly meet ups involving this same woman but some financial stuff too) leading to endless counselling about trust etc.
Conclusion: I should have stuck with my gut feeling early on (but then I wouldn’t have DD).