i felt left out.

Sorry to hear that. Perhaps communicating better and clarifying to them will be helpful. Sometimes people make assumptions or they feel they are bothering you now that you have new responsibilities. It’s good to trash it out and let them know you wish to be included in future planning of meet ups and will always try to make it. If all else fails, get to know new friends! Or get to know friends whom you’re not that close with better. You never know what you’ll find :) all the best

You better to communicate with your friends. They might think that inviting you for such events may cause you a trouble. because you have baby to take care. and other thing is life style of most of mums change after having baby. So have chat with your friends and let them know that you are really willing to join with them and you can manage it time for it.