It probably sounds a bit "clinical" but I'm trying to be clear-headed and I am a bit clinical anyway... and I have got to the "let's get married or I'm leaving" stage.
To me, these are non-negotiable:
-Either parallel careers with no children involved; or complete partnership with children, including legal committment, wills openly agreed upon, etc. Under the parallel careers option I would be pretty hurt if we didn't openly agree on finances and wills, but autonomy could be possible.
-Full economic partnership, pooling resources, unless there's a strong reason to do otherwise (eg one has debt or gambling issues).
-A declared partnership (in our case, marriage) means backing each other up, supporting each other first, presenting a united front in the face of criticism, be it from my mad family or from his family who dislike me. I have no problem with discussing things in private together, and no problem with being told I need to change my behaviour; however, I'm also capable of recognising when someone else is behaving inappropriately.
-If we have kids, this entails agreeing in advance how to do the important bits of parenting (such as what messages we send by what we praise, what behaviours we model and what behaviours we try to adjust in ourselves, what the ground rules and consequences are for behaviour, basic health and nutrition); backing each other up openly; and being consistent and transparent with boundaries, both with children, and with "participating and enthusiastic" 
grandparents.
Background -
We have been friends since undergraduate uni, together nearly 7 years, living together for 6. We are both 36, so if we are going to have kids we need to get on with it. We have recently moved from stressful, high-powered jobs in London, to sabbattical in [nameless laidback forrin country a long way from London], and for the first time in years, we have had enough sleep and can think straight enough to actually begin to discuss the future. I had a pregnancy "scare" a few weeks back and it didn't seem too scary, it actually seemed like quite a good idea (to me, before I tried to talk it through with DP). We are thinking of staying here and not returning to the UK, since we have the right to live and work here, and family are in the neighbouring laidback forrin country.
DP is a bit of a mummy and daddy's boy. This is good, in that his parents are lovely, very sensible, very high-achieving. However, it is totally clear that if he had to choose between me and his family, he would choose his family every time. His parents think I am a waste of space, partly because I don't get on well with my own narcissitic, screeching, grabby and abusive family, and partly because they don't like the fact I've "failed" at my career. They were perfectly happy with "our son's girlfriend the surgeon" but now it's out in the open I'm thinking of not going back to medicine, it's "oh our son has lots of women friends". And all DP has to say about that is "my parents aren't comfortable with your decisions and don't want to be drawn in and forced to take sides in your problems with your parents".
Our discussion of the future yesterday did not go brilliantly. He basically said that his attraction to me is either as a high-powered autonomous career person (in a career that i want to give up because I hate it - and have currently dropped out of), or as the mother of his children. He is not interested in marrying me or economically supporting me, as anything other than the mother of his children. He doesn't want to marry my "issues" with depression, my abhorrent family, my career midlife crisis, and all that's apparently what has stopped him from proposing in the past.
I said I wasn't totally averse to having kids - he said he would absolutely love to have kids. I asked what he thought having children would involve, tried to make it clear the right answer is "support each other through thick and thin, total partnership, backing each other up in adversity". I asked how he would respond if I got postnatal depression, we had financial problems, if the hypothetical baby had problems. He didn't answer.
So basically, he wants the good bits - my economic independence, my autonomy via my career, and my ability to carry and bring up his children, on my own. But he doesn't want to support me, only his own hypothetical children. And from what I've seen with our extended families and kids of friends, at every turn, he wants to be able to choose whether to play with the kids, or do his own work - he backs out of anything other than playing. At the moment, he is not bad re housework - he doesn't show initiative but does it if told what to do. He is fine with being told what to do. However, he would need initiative if there were children involved, and I've never seen him display initiative with respect to anything outside his work.
I don't think this is a good start to marriage and children, and am considering trying to set ground rules - which will be the basis for me leaving the relationship, within the next 6 months, if they are not adopted.
Is this too harsh? (sorry it's so long)