I feel your pain. I have a 5 1/2 month old boy and he is having sleep issues too. My husband also stays and home with him during the day while I work. Before I went back to work, I had Tyler going to sleep in his own and sleeping through most of the night. Since then, it has been downhill as my husband uses any means necessary to get him to sleep. He will not let him cry.
Two days ago, we went to a new pediatrician and they gave me some pointers. They said to lay them down drowsy and pat them on the back for a few moments. Then, if they cry, let them cry for 20 minutes or so. If the crying seems to be letting up, then let it go. If not, check on them and reassure them every 10-15 minutes.
We altered this method a bit and it seems to be helping. We put him in his crib at naptime/bedtime and let him play until he gets cranky. Then, we give him a pacifier and pat him on his back till he doses off. We plan to adjust this along the way. Once he is going down easily, we will stop patting his back.
I do not like hearing him cry but I think 20-30 minutes will not hurt him. Sometimes, if we let him cry for about 10 minutes, it wears him out enough that when we come back into the room and pat his back he goes right to sleep.
I hope this helps.