As Blessed John Henry related years later to Dr Pusey, on August 22 1845 [Pusey's birthday, Octave Day of the Assumption], Newman first "saw his way clear" to put a Miraculous Medal round his neck.
The phrase reminded me rather of how Archdeacon Manning, six years later, did not say his first Hail Mary until he had formally resigned his archdeaconry and walked across the bridge to say his prayers in Southwark Cathedral. Marian devotion seemed a dividing line in the sense that, however one's theological views might have developed, it somehow didn't seem right to do certain things while one was still 'eating the bread' of the Established Church.
August 22 was some weeks before that rainy evening when Newman threw himself at the feet of the dripping and steaming Fr Dominic Barberi and began his two-day long General Confession. Clearly, on that August day, Newman saw himself as having turned a corner. I wonder if it could be anything to do with the fact that (he was already familiar with the use of the Roman Breviary) he had just celebrated the Octave of the Assumption with its Marian readings at Mattins (rather more of them in the 1840s than in the circa1962 Breviary).
I have heard the fascinating suggestion that the Cor ad Cor loquitur of Newman's motto referred to the Sacred Heart of Jesus and the Immaculate Heart of Mary as they appear together on the back of the Miraculous Medal.