Might the Blackfish have changed his opinion on marriage? [Spoilers PUBLISHED]

I’ve recently read through the series for the first time and was reading some of the Blackfish theories and haven’t seen very much discussion of a potential marriage. I’m not sure I’ve fully grasped all of the political implications of marriage in ASOIAF quite yet but it seems to me that the Blackfish has a huge amount of loyalty to House Tully despite his refusal to marry to this point and is the ‘rightful’ (not sure the correct term there) heir to Riverrun. That is especially meaningful I would think with Edmure in custody. Could it be so simple as Brynden Tully being unwilling to marry unless out of necessity to House Tully, which he views as now being the case having gotten married/betrothed in secret by the end of ADWD?

I have no idea who the Bride would be, Bethany Blackwood sprung to mind with them both being mentioned in the Jaime ADWD sample chapter and Tytos’ unwillingness to part with her as hostage but can be discounted due to age since IF Brynden were to marry it would certainly require immediately attempting to have children. I guess it doesn’t really matter though who the Bride is for the purposes of this discussion—the point being that Brynden having legitimate sons would greatly strengthen the Tully succession.

Apologies if this is asked and answered— I’m new here and tried to find old posts on this but could have missed something.

I’m going to get out ahead of one thing having been an internet user for many years (not yet sure how this sub rolls) but Brynden taking a hard stance against betrothal or having said he will never marry in the past + that being out of character from what relatively little we know about him is not evidence to me that it won’t happen.

I’m also curious if he could be the POV for the prologue but that would probably be a totally different path for GRRM to take than the one above and is maybe a discussion for another thread but if that’s totally crazy or impossible feel free to tell me why I’m wrong.