The question comes up a lot I guess.
And it really is down to you. Everyone will just say keep it, regardless of anything going on in your life. If someone doesn't have to pay for it then they will tell you anything. You always get your mates saying 'just buy this' 'just buy that'.... Well yes, obviously you're going to say buy this and that because you ain't the one paying lol!!
Is it worth it?
There's two ways to look at that question. Financially, fuck no it's not worth spending all those thousands of pounds on a 1.3 1990's car lol.. You'd have to be an absolute meth addict to look back and think fuck yeah 15 grand so far and I can justify every single penny of it. Just no.
On the flip side.. It's worth it because it's a sense of achievement of coming so far with it. When you drive it, the way it makes you feel. All the bad things disappear and all that matters is there and then.
But you know what man, only you can decide which way you look at it. It's your car, your money, your family, your choice!
People here can only guide you so far, and give their opinion (which is 99.9% be to keep it lol).