How can we tell if we love God? True love obeys Him.
So how do we obey? Christians are to love God and each other, and indeed everyone.
'A new commandment I give to you, that you love one another, even as I have loved you, that you also love one another.' (John 13:34)
'If you love Me, you will keep My commandments.' (John 14:15)

Love for Jesus is shown in our love for each other.
'This is My commandment, that you love one another, just as I have loved you.' (John 15:12)
We love each other unconditionally. No strings attached (Eg. I'll love you if you do this or that).
'You are My friends if you do what I command you.' (John 15:14)
We are to obey by loving, not doing certain things, keeping certain days or going to certain places.
'This I command you, that you love one another.' (John 15:17)

'Truly, truly, I say to you, if anyone keeps My word he will never see death.' (John 8:51)
Do we listen and love. Treasure his word and love each other.
'He who has My commandments and keeps them is the one who loves Me; and he who loves Me will be loved by My Father, and I will love him and will disclose Myself to him.' (John 14:21)
'Jesus answered and said to him, “If anyone loves Me, he will keep My word; and My Father will love him, and We will come to him and make Our abode with him." '(John 14:23)
The problem with some is that they believe that they are the only channel for revelation from God and others are somehow, 'not of Jesus'. Sounds a bit like the Watchtower Society to me.

'Above all, keep fervent in your love for one another, because love covers a multitude of sins.' (1 Peter 4:8)
'We are not a perfect people but we are a pardoned people' (The late Pastor Les Knowles)

'...but whoever keeps His word, in him the love of God has truly been perfected. By this we know that we are in Him' (1 John 2:5)
'For this is the love of God, that we keep His commandments; and His commandments are not burdensome.' (1 John 5:3)
He has taken the burden upon himself and taken it from us.

'This is His commandment, that we believe in the name of His Son Jesus Christ, and love one another, just as He commanded us.' (1 John 3:23)
'The one who keeps His commandments abides in Him, and He in him. We know by this that He abides in us, by the Spirit whom He has given us.' (1 John 3:24).
I am so glad that God's Spirit witnesses with us that, as Christians,  we are his and this is confirmed and established in his Word.