I do believe those who are born again believers experience great freedom emotionally and ontologically from sin. The language in Ellen White is over the top. I believe Jesus asked us to strive for perfection (not to gain) but “because” we are saved and loved by God. Freedom from sin should be what we all desire. John wrote “I write these things that you may not sin, but if you do, we have an advocate with the Father-Jesus Christ, who IS righteous.” 1Jn 2
The idea however that we will not need the mediation of Jesus at some point is, to my mind, heretical!
It is nowhere found in Scripture, and it actively negates the power of the Cross and the true Gospel in the believers life. “I, with God’s help, in the end, save myself.”
We are perfect when we are glorified and the second coming of Christ, so says Scripture:
Read the following Scripture from beginning to end 7 times and you will understand:
"Our life is hid with Christ in God. When Christ, who is our life, shall appear, then shall we also appear with him in glory."