I agree that the thoughts of an SP who gives her personal number out to you is both flattering and great for the ego, but you have to think about whether or not she is REALLY good at her client retention skills or she really cares/likes you...??
I will admit, that I've fallen for the same thing but have tried to keep that line drawn in the sand; yes, it was great for my ego, but when you have SO and family to think about, it's not a line to be crossed. The SP, thankfully was very aware and did not cross the line with unsolicited phone calls and texts, although during my elation period, I did text her a couple of times until I realized that this was not a smart thing to do...guilty.
Call the SO and tell him straight up, "I won't be seeing your girl anymore and not interferring in your lives. I've obviously crossed the line and this will not happen again" If he's threatens you about anything, that's when I would pull the "I can have you traced and reported.." card; I also have a recording device for recording cell phone calls (20bux on most online shopping sites). Thankfully and hopefully he does not know where you live and any other vital info other than your cell #.
Just my .02