I've name changed - I've posted about this before about 4 months ago and the general consensus was we were stuck in a rut and he probably wasn't cheating.
However, I've just signed us up for online billing with our mobile (joint accounts) and I took the opportunity to look at his bill.
There are 2 numbers that are suspect - neither are in his mobile address book. One he texted only 5 times and the other he called twice @ 00.34 and 01.40am.
How do I find out who they are - have called both go straight to voicemail.