I've learned at my age, after years of trial and error, that I am always the happiest when things flow. When I am myself, this applies to all my situationships as well. My favorite female companion is a pleasure; she is easy-going and appreciates everything I do - the bulk. She exercises daily, has a gym physique, is curious and intuitive, eats the way I do (unprocessed), has constant, raucous, and delicious sex with me, and is communicative. It makes for an easygoing situation in all ways. Am I bored with her? No, it's been seven months, and when I see her, I instantly get aroused, clothed or not. I often wish she was still with me when she's gone. There has never been a moment when I've not wanted her that way.
Why do I feel this way? Because I can be myself with her, and she definitely notices when something is off and adjusts instantly. I do as well, to a certain extent. I like to say that I am about 5% mutable. The remaining 95% of me is me and will not change. That 5% is what I leave in place for relationships, little adjustments I'm willing to make to create harmonious interactions.
Why would you want to lie about yourself or act incompatible with your standards and beliefs? Garbage in > garbage out. If all you're interested in is an ONS, as some are, then lie - if it's that important to you. I prefer to live life on my terms, not someone else's.
Do I conduct physical relationships with women, unlike the woman I described above? I have many times. Did I enjoy them the way I want the woman above? Not. They all require compromise from me, more than I'm often comfortable making.
If you suck in general, make yourself less sucky, but if you find yourself needing to act a role or feel like you have to, you have a lot of internal work to do, ever indeed, to be happy.
Happy and confident men get laid. Plain and simple.