Mid 50s couple here, not into cuck but we do enjoy mfm with a long term friend, many many times with him.
No humiliation at all, we take turns with her and we all have a great time.
We don't use rubbers and we both cum in her.
Him and or I have no problem kissing her after she kisses other guy, she loves to kiss us back and forth. We both have kissed her after she's swallowed a load, not right after but a min or two later no problem, yes I can taste it.
We've both gone down on her after one or both of us has cum in her, she wipes off so it's not all over her down there but it's there for sure, we do it because she likes it.
My absolute favorite is watching them get it on till he unloads, I mount her and start while she cleans his dick with her mouth then we kiss while we fuck, nothing more exciting for her and me.