Any advice am I wrong?

Me and my child’s father broke up after our baby was 5 months old and we now have a three day on and off schedule. He’s 9 months now and we’re trying to have some type of relationship when his daughter is not there which is only so often. So whenever me and my son leave for my days I really feel some resentment because basically I feel like a lonely single parent just because of his daughter and she doesn’t leave till may. I know he says we can still live together but I know that will create problems and I’m just mad for him letting it get this far
Any advice am I wrong?
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