If you read the back history of this board, you'll find that skips have been hired on numerous occasions...
Have you cleared your house of everything that has his name on it? If not, that's how you're going to fill the time between your mumsnetting and dog walking for the next couple of days.
Chuck all of his stuff randomly into bin bags - there's no need to fold clothing or fnd boxes for breakables - and dump it all in the garage.
Once you've accomplished that task, text him to say that his gear will be available for collection between, say, 10am-4pm on a day of your choice later this week and, if not collected on that date, you will arrange to dispose of it by skp or other means. Leave the garage open on the appointed day and take Bully out in your car (he'll fit in one way or another) from 9.45am-4.30pm.
It has to be done otherwise he's got an excuse to pop round whenever it suits him - and you don't need the temptation of begging 'talking it over' and trying to explain yourself/understand why he left.
A garage that's free of clutter will give you the satisfaction of having reclaimed space that rightfully belongs to you, and you'll be able to safely house your car overnight while sparing the odd thought as to how the ow's 'oasis of calm' may now resemble the tip he left you with.
And that's before he starts 'improving' her home - as he will. In fact, for all you know, that's part of his attraction for her - she might be congratulating herself on having landed a bloke who's 'handy' and will solve all her house maintenance requirements. Let her have her dreams... we know they'll be shortlived.
As for being 'friends' with him, nah, of course you can't regard him as a pal. Maybe in a few years' time after you've completely moved on from him - but, by then, he'll mean nothing to you and you won't want to know him.