How do i communicate with partner. We used to communixate all the time and in the past 6 or 7 months…

How do i communicate with partner. We used to communixate all the time and in the past 6 or 7 months there is none. We live together and i have an 8 year old son. And the communication is just not there anymore. Weve only been dating for 17 months. I know some pf the problem is me, because i put it off sometimes. Its hard to talk about whats going on with me or my feelings or what i want or to ask him all of those things. I never know where to begin.