A good motivation is riding with mates. They will be faster than you uphill due to the ballast. Lose that and you’ll keep,up with them.
Or enter a hilly event on the bike in a few months, there’s nothing like sweating up a hill to motivate you to lose weight.
I’ve done both, I ride with a mate regularly and I’ve entered the etape Cymru in September. It’s keeping me off the biscuits and on the bike because I don’t like being a slow sweaty mess!
Good luck mate.