Hi - I've been travelling alone with my dog for years both here in Uk and for longer duration trips in Europe. I spend 2 - 3 months a year somewhere in Europe, usually from March onwards so I'm home for the wonderful (haha) British summer but mainly to get back to uk before it gets too hot for my dog. We've travelled extensively through France, Italy, Spain and Portugal - not ventured any further away as there hasn't been any need - there's so much to see in those countries alone.
Just pick up "all the Aires" for France ( as wherever you're heading, you'll go through France) and "All the Aires" for whatever country you're heading for.
If it's your first trip abroad, stick with France as it's geared up for motorhomes,
DON'T use motorways and park amongst other motorhomes ! You will meet many Brits doing the same and you'll make friends with folks from many countries.
If you're sticking to UK, join one of the Clubs and use their sites and certified sites/locations + of course the NIGHTSTOPS scheme. Again, you will meet lots of people and make many friends - Enjoy
PS - As a lone traveller, if you're over 55, The Camping and Caravan Club gives you a discount and if you don't want electricity (why would you) you can get an "unserviced" pitch for a few quid a night with full use of showers and toilets