Biblical literalism screws up everything (except tithing income and conformity and ability for priests/ministers to control the flock), so this too.
Which is why life and spirituality do a lot better if you go with its origins, not it’s Middle-East-religious-war versions.
“God is love” in Biblical literalism can come across as part of the awful “God has all this holy stuff, basically everything good, but humans are doomed shits until they accept Christian dogma and grovel to our lovely loving God who will otherwise send them to eternal inescapable torment.”
“God is love” even in the actual historical Jesus version was probably meant more like a way to help people tune into their loving Buddha nature. God is the universe and everything, and there’s love at everyone and everything’s core. In that perspective, love between two human beings is part of everything (and so part of God, since God is just a metaphor for everything), so in that view it doesn’t belittle it except inasmuch as it points out that the universe is a lot bigger than a couple, and includes unimaginable amounts of love, too. You might also start to notice what of the love between two people is love, and what is actually attachment or projection or programming or attraction or whatever, but that’s not a contest, it’s a perspective that can help develop the relationship.