That is exactly how I feel. All I ever wanted was to have a family, but I'm just too unstable to cope with relationships and I knew I couldn't be a single parent, so it just never happened. Now I'm older and wiser, I accept that the risks were just too great. Passing on depression to my children (either through faulty genes or faulty parenting) and the likelihood that my children would become my carers are things that I would have never been able to forgive myself for. Insight doesn't stop it hurting like hell though.