Help with parents after new marriage

Ok so it I know it just screams first world problems but here it is .

My parents are pretty well off but constantly work hard for their money. They've helped my new husband and I throughout the years and they know our appreciation but we feel that since we are married we shouldn't

necessarily accept their financial help.

Situation: my husbands car died after work so I told him to just take my car and I'll stay home since my wages don't compare to his, plus I'm only part time.

My father is insistent on us to rent a car, pay to have the second car fixed and later buy another car on his dime.

He's been so used to financially helping my older sister and her family so often he's literally throwing a temper tantrum when I told him " we are ok, we have a plan to handle the car situation for now ." We both agreed to the fact that my parents can't rescue us for the rest of our lives, and want to break them , mostly my dad , of the habit.

Now mind you we are going to see the fertility specialist this week. We have that covered but we've talked about that since I don't make very much that if we have one successful pregnancy that my wages would barely cover child care. So we agreed that when it does happen I'd stay home. My dad doesn't know this side of the plan and honestly I don't see it as his business to know.

I don't know how to politely break his heart and let him know 1) they can't rescue us ALL the time 2) it's a test of our marriage to struggle a bit beyond our fertility 3) the insistence of handling our car situation is essentially emasculating my new husband in this marriage...

I really need advice on this.

Daddy can't always save the day and I don't want their help looming over us because we take it to put THEM at ease....

please help