nearlythree - you have hit the nail on the head, if you aren't happy, your hme isn't going to be...no matter how much decorating, soft furnishings you throw at it.
But, in the meantime, while you work on you and dh, there are some things you can be doing.
1: Cleansing - someone mentioned smudge sticks, but IME, use whatever you have - incese sticks would do - sometimes it's about the intent and the ritual rather than the accessories IFKWIM.
have a look at some hints here
You could also have a family session, where, having cleansed each room, everyone takes a noisy instrument (bells, drums, whistles and ,arch round every corner of the house, making some noise, visualising any bad vibes being driven away, before sitting down to a special family meal.
2: Create a blessings tree. Could be a large pot plant, or some gold sprayed branches/willow wands whatever. Write down anything you have to be thankful for, anything which has made you feel positive (Start small if you find it difficult to think of things, eg a nice afternoon with the family with no arguments; a lovely meal you have enjoyed; a compliment from a friend) and hang it on the tree. You can roll up the 'blessings' if they are 'private'. Also add any 'thank you' cards etc you may recieve. Try and find one thing a week to feel thankful for and encourage children to do the same.
3: Positive visualisation. Sit in a room/area of room where you currently feel sad or uncomfortable. Light a candle to help you focus. Clear your mind of everything and imagine yourself bathed in warm light; as you breathe, imagine the warm light flooding through your body and then out into the room, filling every inch of the room in a warm, comforting glow. Concentrate on capturing happy feelings (again, start small if it's hard for you - the smell of your children, being cuddled) and project those feelings into the room.
if this is too new agey for you and not what you are looking for, apologies. i hope someone else will have some more ideas for you. Blessings x