Yo Ash, wanted to say firstly i'm sorry to hear your birthday ended up being a quiet one this year, and wasn't what you were hoping for.
The only second thing i wanted to say was don't beat yourself up too much for it - you already got the awareness to know it was a mistake & regret doing it, though overly hating on yourself is only going to feed the depression and that in turn just cycles you back down into the bad habits you're trying to prevent.
Take a moment to appreciate that you did well to recognise months ago you had a problem and you actively took steps to self-exclude. Since then you've managed a good few months of internal discipline, which in the face of any addiction is still an impressive feat - everyone on that road will stumble a few times, and many would've broken alot sooner.
Allow yourself this error of judgement and take it as reinforcement of the fact that nothing has changed since you last played; you already know the casinos still win everything & we still lose everything - it just proves you were correct to self-exclude & stay away. You may have spunked £60 now but think of the money the past few months of self-exlusion has saved you, and that it is your actions which saved that money. Staying healthy & positive now puts the power back in your hands to save even more money over the coming months too by continuing to stay away - and the key is to remember you both have a future AND deserve to have that future too. It's an old cliche, though the past is the past; we can only effect our futures.
It does often seem shit trying to stay away from easy habits, though you're allowed to have some pride in the resolve you have already shown & use that to boost your confidence that even despite a few stumbles you can keep yourself on track for where you want to get to. Wishing you a good Spring dude!