From what my doc told me, the salvage radiation itself does not usually make things worse in continence or ED department, but it does stop progress. That's why they prefer to wait a bit to let things heal. Radiation does not reduce libido, as far as I know, but if used in combination with HT, hormones do.
As you see from my stats, I am in somewhat similar situation, except for the lymph node. The radiation doc recommended hormons AND radiation as it has a better chance to kill off stray cells than either treatment alone. He especially mentioned that for pelvic radiation (I assume that your SO is going to do that, given the positive lymph node) the doze that can be safely delivered is smaller and the radiation needs all the help it can get (i.e. hormones).
You also may want to find out the post-op PSA prior to radiation regiment.
Father died from poorly differentiated PCa @ 78 - normal PSA and DRE
5 biopsies over 4 years negative while PSA going from 3.8 to 28
Dx Nov 2007, age 46, PSA 29, Gleason 4+4=8
Decided to participate in clinical trial at Duke - 6 rounds of chemo (Taxotere+Avastin)
PSA results: 1/8/2008-33.90, 1/11/2008-29.50, 1/31/2008-38.20,
2/21/2008-32.00, 3/13/2008-26.20, 4/3/2008-26.60, 4/24/2008-20.60
RRP at Duke (Dr. Moul) on 6/16/2008
Pathology: Gleason downgraded 4+3=7, Duke: T2c N0MX, one positive margin,
2nd opinion at Sloan Kettering: T3a N0MX, extraprostatic extension, two positive margins
PSA undetectable for 8 months, then 2/6/2009-0.10, 4/26/2009-0.17, 5/22/2009-0.20, 6/11/2009-0.27
6 Months ADT: Casodex started 6/12/2009, Lupron 6/22/2009, PSA 6/25/2009-0.1, T=516
IMRT to start mid-Aug