I’m sorry your trust was violated. Your traumatic experience where your trust was violated shouldn’t be used as a warning label for others. There is no reason to advocate that other people behave as if their partners are unfaithful without prior evidence because you personally were wronged in a deeply hurtful way.

It is important to healthily evaluate what is a relatively uncommon but seriously hurtful thing that happened to oneself and how that distorts one’s understanding of what’s normal behavior in intimate relationships.

But how else are you going to get evidence? Doing a paternity test is the act of gathering data which could further be used as evidence of faithfulness of your partner.

Or else it's just blind trust without any firm footing in reality.

If you can't be arsed to do the test for a ONCE or TWICE in a lifetime kind of event with long term consequences because you somehow feel hurt that your partner isn't a fool who builds his life around blind faith.. well, there's not much to be said...

This is a trauma response style logic where the bad/harmful thing is the default and the healthy thing needs to be proven. The fact of the matter is that cheating to the point of clandestinely having children is abnormal and unusual. It isn’t blind faith that your partner is faithful; your partner will show you their faithfulness just by the act of being your partner. It’s not staying out without explanation. It’s emotional engagement with the relationship. It’s transparency when things get boring. It’s the labor in keeping the relationship fresh and interesting. Overlooking this to lean towards mistrust also devalues the labor of your partner and shows your bias towards past trauma. I understand this thing is big stakes and is very hurtful, but even grand hurts doesn’t justify no longer paying attention to basic reality for over-cautious behavior.

There's no trauma response, data suggests that cheating is common. Thereon following through with the baseless assumption that this totally won't happen to you is downright foolish.

All this wishy washy pretense about "emotional engagement" comes off as super dishonest, just to weasel your way out of doing a test (which should be a standard procedure anyway).

That's one of those times where the faithfulness has to be put to test.

Trying to weasel your way out of doing it via emotional manipulations is more of a red flag than anything.