When you’re being sincere, people can sense it. When you’re not being sincere people can call your bluff. For example, your boyfriend broke up with you for whatever reason and they want you back because of xy and z… Normally you can tell if the first apology was sincere or it’s the same crap they feed you time after time; it’s the same excuse. At this point they are not being sincere, they don’t want to be alone so they say the same thing that got you back the last time, hoping it will work.
Sometimes you have to wake up and smell the BS. If you truly love someone, why put them through the same crap? That’s not love, that’s self hate, and being insecure. This person is a sadist, they enjoy watching you suffer; it’s really sick if you think about it.
Sometimes you have to choose “YOU“ first for your own sanity. Give them sometime to grow up and be a better person, until then keep choosing YOU now that’s being Sincere.