Certainly he lampooned the Duke, and he was never weary of writing insultingly about the other.
Most probable is the account given by Lady Louisa Stuart, Lady Mary's grand-daughter, which is to the effect that Pope made a declaration of love, and that Lady Mary received it with shrieks of laughter.

If Pope were serious, it must have galled him indeed, though nothing can excuse the malignity with which he pursued her for years and years.

And if he were not in earnest, he would probably have been nearly, if not quite, as indignant.
Anyhow, it is a sorry story, and a blot on the scutcheon of the poet, who, good-hearted as he usually was, was cursed by the gift, refined to a rare degree, of alienating his friends, more often than not for some fancied slight.

Addison he lampooned, and from Dennis and Philips he parted company.

"Leave him as soon as you can," Addison had warned Lady Mary.