I remember being told a story once by an anarchist I knew from online about a radical who met another radical at one of those anarchist bookfairs. It turned into a relationship, lasting for about a year iirc, with the two of them committing a series of escalating acts that eventually lead to her suggesting that they do some kinda infrastructure sabotage. This was the point where she revealed herself to be a fed and had a lot of proof on this guy to put him in jail, though depending on the situation, someone in this kind of position could also be forced into being an informant

the moral of the story is that feds will go yo great lengths to infiltrate radical groups and entrap people and that you should be careful about who you trust