feel very left out ...husband spends no time with me...

Kenny,
Looks like your h wants to spend time with you and kid but wants to please mom too.
why don't you make plans to meet him at work for lunch. or if you are with baby maybe a park so baby can enjoy too. if you guys don't tell your mil how will she know. outing is not doing errands. those things you can let your mil tagalong or just let the mom and son do it so you can relax at home with the baby.

 

don't sit in your room.sit in hall by the time he comes and call him and often involve him in activities.if you are about to eat dinner,give baby to your MIL.definitly she will take of the baby before son.

Once your husband comes,give baby to your MIL more often and take care of your husband needs and slowly involve your husband with baby needs.

 

Ignore and he will chase.
Be independent. Get dressed very beautifully. Go to your friends house or the park or to a hotel with your baby. Don't even ask your husband to come. Come home 15-30 minutes after you say you will be back and tell him oops I was having so much fun I forgot the time.
Once in a while place your baby in your husband's lap and tell him you are going for a quick shopping trip.
Go out to a girls night/day out. Just go grocery shopping. It doesn't matter where you go. As long as you dress up well and look happy when you come back. Don't give him any information about your trip unless he asks for it.

Don't ask permission, don't invite. Just inform and leave.
Since he doesn't spend time with you, you value his company and long for it. And since you are begging for his company he thinks that you are always available and doesn't value it enough.