Can someone genuinely love you, but cheat?
Their 'love' would have to be quite shallow, wouldn't it? Superficial. To be incapable of seeing that their cheating would hurt the person they claim to love.
So it's a NO from me.
If they're willing to cheat, to prioritise fleeting sexual gratification (or worse, a second relationship) over what should be the foundation of their joint life with their partner, then their relationship is not founded in love, but in - convenience.