Reformation Sunday- cause for celebration?

I have recently learnt about Reformation Sunday and I must say that it leaves me feeling rather uneasy.

Firstly, let me state that I am not ecumenist. One of the reasons I grew discontent with the Church of England was its embracing of mutually-exclusive beliefs as Truth. I have very firm beliefs about what the Church is and where its boundaries lie. However, I do not believe that God is restricted to the Church and that he can bestow his grace outside of it (although it is not my place to state definitely that he always does). I also believe that some degree of Truth exists outside of the Church (although not in the fulness in which it is to be found in Orthodoxy), and that the majority of Christians outside the Church are people who are genuinely trying to live in accordance with God's will to the best of their knowledge. Because of this, I find the hostile dismissal of everything outside of Orthodoxy by some Orthodox as slightly distasteful, and which is why I was interested to hear of Reformation Sunday.

Now, I have said before elsewhere, that, while I have respect for people's right to hold whatever views and beliefs they wish, if I believe those views to be wrong and affirming of fallacy, then I cannot respect the actual views. I can usually do this with some degree of indifference. However, reading about Reformation Sunday actually leaves me feeling rather unwell. The reformation achieved the following:
- the acceptability of the denial of aspects of God's revealed Truth within Christianity.
- the furtherance of teachings contrary to the Faith within Christianity.
- the primacy of the individual conscience over the teaching of the Church where the two conflict.
- excessive pain and suffering.
- numerous deaths.
- 500 years of further division among Christians.

Now, I have seen other commemorative days for events of the past, among them, the regicide of King Charles I. Some editions of the Book of Common Prayer contain a service commemorating the day, and it is clear from the prayers of this service that this is a service of penance and reparation for the murder of the King. However, by contrast, from what I have read of Reformation Sunday, it appears to actually be a celebration! I am really struggling to understand why any Christian would want to celebrate such a thing. Even if people disagree with the first three of my points above, surely the last three are reason enough for this not to be a time of jubilation. The sad and tragic effects of the reformation are still felt to this day, as I'm sure we are all too aware.

This coming Sunday, I shall be remembering all of this, and my prayers on that day shall include petitions for the unification of all Christians, and that within our Mother, the Catholic and Apostolic Church. I invite you to join me.

From Good Friday in the Sarum Missal:

O Almighty everlasting God, who savest all men, and wouldest not that any should perish; look on those souls which have been deceived by the fraud of the devil, that, laying aside all malice and heresy, the hearts of the erring may learn wisdom, and return to the unity of thy Truth. Through Jesus Christ our Lord, who liveth and reigneth with thee and the Holy Ghost, one God, now and unto the ages of ages. Amen.