I find this thread very sad :( I have never felt my life was not enough.
I have experienced unhappiness of course and I really think those years of having two or more young children (toddler and preschoolers) can be enough to break the most optimistic of people! Now they are both at school I am much happier as life is less stressful. We have suffered huge amounts of debt (about £80k) which we have spent the last 10 years paying off and are 2 months away from completely clearing. Because of this we cannot afford our own home so have had to live with parents which has been very draining. DH has worked his arse off to get to a good position in his career (and he is finally there). But it has taken working weeks of 12+ hour days (sometimes 6 or 7 a week), he rarely takes any of his holiday allowance and we have never had a family holiday until this year which was camping in the rain (although next year we will have a proper one abroad I hope!). So things have been far from perfect in the last 10 years since we got together in our early twenties.
However I have always enjoyed my life even though I have not really done much of note
.
I travelled for a year in my early twenties which was great fun and one of the best things I have ever done. I did not go to Uni as I had no idea of what I wanted to do so just did random admin jobs until I had DD at the age of 25. I have never been ambitious in that way. My only ambition for myself has been to be happy (and it is the same ambition that I have for my children). What makes me happy? Well the main things are:-
A wonderful partner - I had my share of rubbish boyfriends but I married the man who I could be completely myself with (and I mean COMPLETELY). Oh and who adored me of course 
My children of course :)
Good friends and a fun social life - this is massively important to me and when my children were young and I couldn't get out much not seeing my friends as much brought me down more than anything. I work hard to keep my friendships alive and I organise lots of nights out when others keep forgetting to get around to it
. I have just organised a 4 night break in Barcelona for me and 5 girlfriends next April. Having stuff to look forward to is so important.
A well paid job - I only do part time (16 hours) and I managed to get into book keeping which pays well and is highly flexible.
Supportive family - I am lucky here as we have two sets of doting grandparents who help with childcare several times a month.
A couple of short breaks from the kids a year to recharge and reconnect.
Anyway I am not being smug, honest, I am just giving my impression of how I feel about life. It may not be perfect but I only get this one chance to do it so I want to make it the best time possible. For the future I don't have any plans to be honest. I don't think about it at all. If I get there I will make the most I can with what I have. Hopefully I will be well off enough to travel with DH but if not I can still enjoy it :)
As Peter Pan said "To live, to live will be an awfully big adventure" 