Thanks for your question.
It seems, from the little information in your question, that you are having a specific problem with one person. You are doing the right thing in praying about it. However, particular scriptures, while somewhat helpful, will not sufficiently equip you to deal with this problem and, indeed, any problem of sin in your life. That comes from a broader appreciation of God's word and His plan and purpose with the earth and how we can fit into that plan. It is only when we see "the big picture" that our temptations, by comparison, become small and manageable.
To do this, I suggest that you enroll in the free online Bible study course available on our website,www.thisisyourbible.com.This course will give you a background in the major themes of the Bible from Genesis to Revelation. As with everything we offer, there is no cost to you other than your time and effort. You will also have a personal tutor to whom you may pose questions either from the course itself or those questions which come to you as you read the Bible.
You asked for some specific scriptures that might be helpful. I have included some below. They are useful but, in the context of a true understanding of God's plan and purpose, they become immensely powerful.
The next time you see this person remember what Jesus said to Peter: But He turned and said to Peter, "Get behind Me, Satan! You are an offense to Me, for you are not mindful of the things of God, but the things of men. Matt. 16:23
I hope you have found this helpful.