Janice,
FindMyPast seems to be behaving this afternoon and so I've made a bit more progress. Would I be right in thinking that your gf married Rose E Compton in Warminster in 1942 and they went on to have a son with the initials TF? If I am right, you will be aware that this son later married, also in Warminster, and had two daughters in Trowbridge, one of whom is named Janice A*. Because of the rules on Rootschat, we must not name or include details of people who might still be alive, so I won't add more, and in any case you will already be aware of all these more recent details.
Rose E Compton was born 15 April 1919, the daughter of Walter J Compton and Annie F Bromham. In September 1939 Rose was living with her widowed mother Annie at 8 Jubilee Terrace, West Street, Warminster and was employed as a glove welter. My guess would be that Henry Samuels was attending a course at the School of Infantry in Warminster when he met Rose. I haven't found a death for Rose Samuels.
It is most likely that in March 1943 Henry left the UK with his battalion and arrived in Tunisia to take part in the North African campaign. Following the Allies success in North Africa the Irish Guards took part in the Anzio landings in Italy. It is therefore quite likely that Henry didn't get back to the UK until April 1944, which was presumably the first time he saw his son. He would only have been there for a couple of months before his battalion took part in the Normandy landings in June 1944.
* Again, without giving the details, I am amused that FindMyPast have transcribed your name from your marriage as James!