How can I make him fall in love with me again

I've been with my so for three and a half years. Recently I feel like we've grown apart. We see each other less, speak less and generally don't do much as a couple. When I express to him how I'm feeling about our relationship he responds by saying 'here we go again' and he says 'would I still be here if I'd lost interest'. I just feel like we're in such a basic robot mode, each day, week and month is exactly the same. We don't live together but there no longer seems to be any excitement. I arranged for us to go on a day out and boat ride but he complained of a migraine and said he didn't want to go on the boat so the day again was just a normal day for us. How do I make everything special again. I want him to show me love and tell me how much he cares but he doesn't really do that anymore. What can I do?