Hi inaheap,
firstly, I think you need to re-order your view of this. If it is manageable at €10 pw, the just chip away at it slowly. You don't want to stress yourself by over-extending it.
secondly, am i right in assuming the debt is no longer accruing interest? Assuming that, at €10pw it will take a sizeable amount of time to get it fully paid off (at a rough calculation between 38 and 39 years). I understand why that would weigh on you. If it were possible to increase that to €15 pw however your debt would be cleared 12 years faster. Double it and you half the time. What I am trying to get at is that if it is possible for you to make a slightly larger repayment the debt will be come less daunting. You aren't going to clear it early and I am sure you watch every penny but it may be worthwhile sitting down and doing the sums and seeing if you could afford more. Perhaps work up to it, say move to a repayment of €12 and keep that for three months, then move to a repayment of €15 and keep that for six months. This will allow you to test your limits in a more cautious way.
It is slow and steady but it will give you a boost because you will be starting to make a difference to the debt and you will be actively engaging in beating it.
Best of luck