Johnstone took the position he had thus made with increasing seriousness, and worked during the Manchester musical season harder than ever. In the summer he went abroad, but not entirely for rest. He greatly expanded his knowledge, and also his musical reputation and that of his paper, by his visit to festivals at Bayreuth, at Oberammergau, at Düsseldorf, and at Vienna. Forced to choose, we have hardly been able, within these limits, to quote from the contributions he sent home. The last of his foreign journeys was unlike all the others, which had been taken alone. The words quoted above from the letter of January, 1902, were no longer to be true, though the desired companionship came late. A solitary life in lodgings, and the absence of domestic ties to one of his affectionate and home-loving nature (which lay behind his gipsy habits) could not be compensated even by hosts of friends; but brighter days were in store. In June, 1902, he became engaged to Miss Lucy Morris, a Manchester lady who had won considerable distinction at Cambridge; and henceforward the most human of interests gave fresh inspiration to his life and work.
Their marriage took place two years later, on June 28th, 1904, quietly at Morecambe. The friend of both, Canon Gorton, married them, and another friend, Mr. Howson, undertook the musical part of the ceremony, which was performed by the Morecambe Madrigal Society and the church choir. There never was a wedding with better music, and for once the hackneyed description, "the service was fully choral," might have been used with a real meaning. The honeymoon was spent on the Riffel Alp: afterwards the travellers attended the Bayreuth festival, returning to Manchester at the end of August, where they went to live at Tarnhelm (named after the magic helmet of the "Ring") in Victoria Park. A few more months of happiness remained to Johnstone. On Thursday, December 8th, he was taken seriously ill, but though in considerable pain he attended a concert in the evening, and wrote a notice of the performance. The next morning his condition was worse, and on Saturday he was operated upon for appendicitis. But relief came too late, and on Friday, December 16th, his sufferings ended. He had just completed his forty-third year: he was in the plenitude of his intellectual powers, and had entered upon the happiest and most useful period of his life.