Hot and cold BF

I have been dating my BF for 4 months and he goes hot and cold on me. At first - I thought it was because we were early and maybe he was still testing the waters. But now - he says he is committed to only me, talks about a future, tells me he is crazy for me, and sends me things he reads about being a stepdad...

But, the very next day - the texts turn emotionless and infrequent. Absence of goodnight texts that are usually our routine. He did this a couple of weeks ago- where he stopped responding to me and told me he purposefully didn’t bring his phone (to avoid me). I feel like I am dating someone with two personalities. I am in love with the affectionate one and am tortured by the other one. I don’t think he is cheating- but who knows? I don’t know if he is just moody and sensitive and doesn’t know how to communicate. I’ve talked to him about it but he hasn’t changed.

I haven’t dated anyone who has done this before. Anyone have experience with this odd behavior? I am starting to think that this may be a dealbreaker despite my attraction to him.