I have been with this guy for almost a year, and I’ve never been happier. Lately he has been distancing himself, he will not go out and won’t talk to me for hours. I have recently been catching up with a friend of mine who I haven’t talked to in a very long time. I have never seen him as more than a friend, but the more I think about it, the more I feel as if I might actually have feelings for him.
I absolutely love my boyfriend and I would never want to hurt him. We always talk about our future together and getting married, but right now I’m having doubts. He has been very neglectful. My friend and I have been talking a lot and every time we do I am extremely happy. Unfortunately he is friends with an ex of mine though. Am I just catching feelings because he is giving me more attention than my boyfriend?
LemonVibe 
What’s happening is normal. He thinks everything is ok and is getting comfortable with you.
Do not start a new relationship without ending this one first. You are already on the edge of emotionally cheating with new guy.
Just go ahead and end the first relationship if you are not feeling it and date around. You are not married and dating helps you learn about what you want until you want to be with one and only one or learn you are polyamourus, (There are rules to that too. Google and educate yourself.)