Does falling in love have to be hard?

For the first time in my life I think I’ve found what I’m looking for and fallen in love…I’m 37 and obviously on both sides it brings with it baggage and complications on his. I have been seeing this man for 6 months now. He has just disclosed that a couple of months into our relationship that he slept with a female friend who he was previously having a physical relationship with but apparently ended the arrangement when our relationship began. He remains friends with this woman and assures me that it was just one night. He is going through a divorce and he stated that he was testing his run at freedom and it confirmed that that wasn’t what he wanted and he loves me to much to lose me. I’m feeling very torn as the thought of ending our relationship physically hurts and he has promised me that it was a ‘blip’ and he wants to build a future with me.
Am I being a weak person if I continue with the relationship?