I'd never thought of needing to find meaning until recently, when I quite suddenly realised that it didn't matter that I don't have children, as I can't / won't be responsible for passing the gene (if it is genetic) or the risk (through poor nurture) to future generations. The fact that there are other depressed people in the world causes me more distress than my own illness, the possibility that I could inflict depression on someone else just by breeding is horrific. That's the meaning I have found.