Spicing up the sex life

I'm new at this an really don't like sharing my thoughts or concerns but after reading some other stories I realized it might be so bad . 
So I've been really thinking that me and my wife need to spice things up, don't get me wrong I absolutely love an enjoy my wife but I just feel as if things are starting to go south. I'm uncertain if it's me or my need to want to do more, lately I find myself thinking about her an another random girl I'd like to have a three sum an it's in her nature so she claims to have at least done it before. I just don't know how to get that jolt of electricity back. We use to have nights man that are just unbelievable filled with lingerie stripper pole role playing and all of a sudden things just stopped. I've tried talking to her expressing it as I thought I should be doing, really randomly I'd ask to eat her out an ill get turned down like wtf 🤔🤔 makes me really think am I not seeing the big picture here did I lose myself in the bedroom? We'd be intimate in numerous ways but yet I find myself always looking an engaging .. 
Some advice would be great .