This separation has been described as diastasis. I have just read about Diastasis Symphysis pubis (DSP) on your web page but this seems to be something totally different. I do not feel any pain ...

Diastasis symphysis pubis (DSP) happens when the gap in the pubic symphysis (a joint that widens to allow your baby to pass through your pelvis) widens too much and becomes unstable. This is rare ...