Oh hon....it can be hard when other people do not treat you as Christ wants them to. But be careful to not fall into that same trap. I do fear that if you let this (and other offenses that will come later in your life) burden you, you will just be weighing yourself down from the spirit out - and that will lead to disaster for yourself.
There have been good things said here already. I just have a few verses to toss in.
To not forgive as our Lord commanded, you are making yourself a slave to what is not good. "Don't you know that when you offer yourselves to someone as obedient slaves, you are slaves of the one you obey--whether you are slaves to sin, which leads to death, or to obedience, which leads to righteousness?" Romans 6:16.
Jesus laid down how we are to handle these situations: "“If your brother or sister
b sins,
c go and point out their fault, just between the two of you. If they listen to you, you have won them over.
16But if they will not listen, take one or two others along, so that ‘every matter may be established by the testimony of two or three witnesses.’
d 17If they still refuse to listen, tell it to the church; and if they refuse to listen even to the church, treat them as you would a pagan or a tax collector." Matthew 18:15-17.
If you want to obey the Lord, you will need to forgive her. "If you forgive those who sin against you, your heavenly Father will forgive you." Matthew 6:14. You say though that you can't forgive her. Not one of us can really forgive anyone - we need to rely on the Strength of our Dad to do that...for we are just branches, but He is the Life Vine! And He will be our will and Strength to forgive! "I can do all things through Christ which strengtheneth me." Philippians 4:13.
And remember to see this as it is...not something that has gone wrong and shouldn't have happened, but as an opportunity from your Lord!
"Who is [
c]there to harm you if you prove zealous for what is good?14 But even if you should suffer for the sake of righteousness, you [
d]are blessed. And do not fear their [
e]intimidation, and do not be troubled,15 but [
f]sanctify Christ as Lord in your hearts, always
being ready to make a[
g]defense to everyone who asks you to give an account for the hope that is in you, yet with gentleness and [
h]reverence;16 [
i]and keep a good conscience so that in the thing in which you are slandered, those who revile your good behavior in Christ will be put to shame. For it is better, if [
h]God should will it so, that you suffer for doing what is right rather than for doing what is wrong." 1 Peter 3:13-17.
But you know what? Thanks for coming here and being brave enough to post this - and how you really feel! Do the same with God....and the Shepherd will lead you out of this and back to walking with Him!