Theology is not black and white. It is not cut and dried, whatever that means (sounds a bit like beef jerky). For most of us, at some point, this supposed fuzziness becomes slightly problematic. We would prefer theological answers to be clear. Why can't the actions of God throughout history and the words written about God be more straightforward and obvious? But...sigh... this is not the case. I suppose this might be one of the reasons why worship can be difficult; worship primarily requires submission, not understanding.
I myself am in a season where I am discovering again what it means to worship the Most High God, especially communally. Sunday morning gatherings in my faith community are rarely an optimum time for me: I am usually tired and trying to juggle any number of things like hauling equipment, setting up, greeting people, rehearsing music, trying to get the right words on the screen, or preparing to give a talk. Musically speaking, the old songs seem a bit ragged and tired, and the new songs are too repetitive and, dare I say, maybe a bit trite? That's just my opinion.
But honestly, there will always be an excuse for why I find worshiping God difficult or uninteresting. Worship, when we honour someone or something with extravagant love and extreme submission, is not our natural posture. And yet, it is. (See, not cut and dried!) We were created to worship, to be in communion with the divine (see the creation story). Because we are dependent beings who long for intimacy with God and with each other, we are, in a way, always worshiping. We are always putting our longing and extravagant love out there. It might be for a new car or a bacon cheeseburger or some beautiful and talented person or a shiny golden calf, but we are always trying to give ourselves to someone or something.
But loving and submitting are hard. Really hard. Because they demand that we not be self-absorbed or self-reliant. When we worship God, we put ourselves in loving mode, in surrender mode, in listening and receiving mode. When we worship God, we unite ourselves with the activity of the kingdom of heaven (that's pretty cool!). Worshiping God keeps us honest and truthful as we bring praises, laments, cries for help, proclamations of God's will and ways, and stories of God's faithfulness to the community. Worship, like any spiritual discipline, is a creative skill which requires practice. We don't always do it well, but that doesn't make it any less valid or worthwhile. Loving someone is a daily exercise. Submitting to another means that we are constantly re-submitting ourselves.
This might all sound like a lot of work, like we have to dig deep to get our worship on (I heard that unfortunate phrase used on the radio this past week), but I believe worship is not first and foremost work; to me, it is more like a mirror. Because God has shown us love, we open ourselves up to him, and when we are in open, submitting mode, we experience more of the extravagant love that God has for us. Our natural response to this overwhelming, unending love is to worship, to reflect the love and glory of God back to him. Worship, in fact, is not something that we pull up out of our inner being; it is gratitude and affection fueled by the extravagant and overabundant love and mercy of our divine lover. In the process of reflecting God's glory and love back to him, we (and all of creation in some way) are touched by this glorious presence of holy love. Paradoxically, when we worship God, when we give glory to God, when we submit our own wills to the will of the Eternal One, often sacrificially, we become unexpected recipients, receiving so much more than we give. This is what extravagant love does.
So the fact that I have been finding communal worship rather uninspiring lately probably means that I need to practice putting myself in an open, loving, submissive posture before God. I can take on this posture of worship (love and submission) anytime, anywhere. No need for an inspiring song, perfectly executed vocals, or catchy lyrics. No need for circumstances to be ideal or my attitude to be perfect. I can simply turn my eyes upon Jesus, look full in his wonderful face, and the things of earth will grow strangely dim in the light of his glory and grace. 
 Turn Your Eyes Upon Jesus. Lyrics by Helen H. Lemmel, 1922.