How do I get the spark back???

June 6th will be mine and my husband's two year anniversary. I'm excited but he doesn't seem to be. He seems more nonchalant about it all.... I feel like he thinks of it as "just another year".... 6 months into our marriage I got pregnant and we were super excited to add on to our family. But after we had our son, it was obvious that the spark had died.... I've tried to initiate sex several times (I seem to always want him 😍) but most times I get rejected... 😒 I just wanna know how I can get that spark back?? When we were dating, we weren't having sex but we had a lot of make out sessions and it was super obvious that he was attracted to me and he wanted me....but now, there's always an excuse. Ex: he's too tired, his body is sore, he worked all day, etc. Ladies, please help me out 😩