If we love God and our neighbor, then we won’t commit murder, idolatry, adultery, theft, rape, favoritism, kidnapping, and so forth for the rest of God’s laws, so love fulfills the law because it is showing a core understanding of what everything in it is about how to do. The greatest two commandments are much easier said than done, so thankfully God gave us the rest of His laws to flesh out what it looks like to correctly obey them. Someone who was correctly living in obedience to the greatest two commandments would be indistinguishable from someone who was correctly living in obedience to the rest of God’s commandments because they would both be following the same example that Jesus set for us to follow.
We should seek to understand what Jesus meant by saying that he came to fulfill the law in a way that his audience would have understood it rather than connect it with an event that hadn’t happened yet that Jesus made no allusion to. After Jesus said in Matthew 5:17-20 that he came to fulfill the law, he then proceeded immediately proceeded to fulfill it throughout the rest of the chapter by teaching how to correctly obey it. According to Galatians 5:14, anyone who has ever loved their neighbor has fulfilled the entire law, so again it refers to correctly obeying it, moreover, it refers to something that countless people have done rather than something unique that only Jesus did.
My problem is not with you speaking about grace and love, but with you doing so in a way the deemphasizes the importance of being a doer of God’s law rather than a way that emphasizes it. For example, you said the we don’t obey the law to try to fulfill its demands.
Jesus set a a perfect example for us to follow of how to walk in obedience to God’s law, so that is what it looks like to have the righteousness of God and to walk in the Spirit.
You did say that we don't follow the law to try and fulfill its demands because that takes self-effort. What you are describing is accordance with Paul’s struggle with the law of sin, not a problem with the Law of God.
Jesus also affirmed in the NT that the way to inherit eternal life is by obeying the greatest two commandments (Luke 10:25-28). It’s going good.
God’s law was never given as something to be obeyed on our own. In Titus 2:14, Jesus gave himself to redeem us for all lawlessness and to purify for himself a people of his own possession who are zealous for doing good works, so the way to believe in what he spent his ministry teaching by word and by example is by becoming zealous for doing good works in obedience to God’s law (Acts 21:20).
The Mosaic Covenant is also grace through faith and the only to become righteous that us testifies about in the Law and the Prophets is through faith in Christ for all who believe (Romans 3:21-22). The context of Habakkuk 2:4 contrasts the righteous who are living by faith with those who are not living in obedience to God’s law. In Isaiah 51:7, the righteous are those on whose heart is God’s law, and in 1 John 3:4-7, everyone who is a doer of righteous works in obedience to God’s law is righteous even as they are righteous, so the righteous living by faith does not refer to a manner of living that is not in obedience to it. God’s law leads us to Christ because it is His instructions for how to have an intimate relationship with him.
No problem, sorry if I’ve misunderstood you.
The point of God’s law is to teach us how to know Him by being in His likeness through experiencing being a doer of His character traits, which are the fruits of the Spirit and why the Spirit has the role of leading us to obey God’s law (Ezekiel 36:26-27). Likewise, the way to love God is by being a doer of His character traits, such as the way to love justice is by being a doer of justice in obedience to God’s instructions. In other words, the goal of everything that God has instructed is to teach us how to love different aspects of His character, which is why the Bible repeatedly says that the way to love God is by obeying His commandments. It is good that you are focused on love and see God displaying it throughout the Bible, but the problem is that you see that as being an alternative to being focused on the story of sin and the law instead of being in complete accordance with it. We can’t focus on needing the life and love of God so that we can be like Him as Children embodied by the Spirit instead of focusing on obeying God’s instructions for how to do that.