I think your problem is a little worst then getting him involved. There seems like you are in an unhealthy relationship. Lovers make love and a lot of love especially in the beginning . I find it difficult to understand how you managed like this for 5 years. Communication is very important here, you need to ask him what he is feeling if he just hasn't have the drive there are lots of medicine out there to help solve this problem. He might be under sort of a stress . Tell him how much you love him and what you want from him. If he won't be willing to treat it then there is something that might be a bit serious then this.