Me and my boyfriend have been together for 3 years and I am his first love, I'm also the mother of his first born son that we had a year after our first year together between before I was pregnant all the way up to me giving birth I found myself arguing with him because he would be texting other females and lying about it, every time he said he was sorry and he wish I would trust him but all of our arguments consisted of me not trusting him I just always felt like he was lying to me, I got fed up and left I thought I would be less misrable if I left but now after 2 and a half months I miss him and he won't even call me and check on me or the baby it seems like he only deals with us when he doesn't have anything else to do it basically seems like he's moving on with his life and forgetting about us I was wondering would the no contact rule apply to me and should I use it? And for how long should I ignore his calls when he starts calling more often to get him to see that life is not so good without us... I'm misrable without him but I don't want him to know that's the way it is... help please...

If he is moving on with his life, why do you need to ignore his calls? He is probably calling for the child you guys have together! You don't need to ignore his calls, just keep the chat on the telephone related to your child you share together.
You left him, so you have to crawl back to him. You dumped him, so he is doing what you wanted, and is moving on.

I think when you have a child with a guy who has left you, keep it about the child and make sure he pays support.

You have shared much but he has other things he would rather do than be responsible.

Protect your heart, and do for your child.

Sort out child support and visitation rights if you haven't already done so.

Keep contact to a minimum,as you will have to communicate about your child.

That was hard to read, you should really use proper grammar.

I guess the jist was you with a guy you can't trust. Other then the child, why would you stay in that situation? There are 3 billion guys on the planet, and several billion of them are loyal and dedicated to one woman so you should consider better options for yourself and the child you created.