Feeling disappointed that you might get a great husband who won’t need you to take care of him except in the ways that come with the territory of marriage generally is not healthy. You should not want your future spouse to be dependent on you, but interdependent with you.
There are many predatory people out there and irresponsible people out there who have their little insect antennae on the lookout for one of those good-hearted souls who can be seduced into “taking pity” on them or “taking care” of them. If the intended victim is someone who can eventually be manipulated into believing the bald-faced lie that no one else will want her or who can be flattered into believing that the manipulator is really as helpless and needy as he claims, so much the better. That alone makes this fantasy a perilous one, something that could set the OP up for a revolving door that takes her through one doomed relationship after another.
This may be so. Still, if it is then we are automatically in above our pay grade.
OP, this is probably a job for a professional. You are right to be concerned that this could affect a future marriage, but we are not qualified to guide you about how to deal with it. If it turns out that you have a habit of guided imagery that you can master instead of renouncing, that’s great, but we’re not qualified to be judges of that. You will want to learn other means of coping with social anxiety, at any rate, and a professional can help you with the process of learning that.