Look love, you seriously need to speak to someone in depth about this.
Go to your local citizins advice bureau as you will be able to speak to someone face to face which I think would be best for you, him and the baby.

Please understand & be clear that their is no way to get ya boyfriend to stay here & no easy way to get him back here

Having a baby will make no difference !!

And once the baby is born, if you move into council house/flat you will be reliaing on public benefits and a requirements of a Fiancee visa are no recourse to public benefits

And with the situation you are in, both financial & residential it is going to be extremely difficult for him to come back as you cannot support him and the government will not!
And I am guessing that he has no money of his own.

All of us on this site know from experience how difficult it is to get a Visa for a loved one and the criteria that has to be met and by looking at your circumstances I seriously do not think that he would get issued one.

I hate to bring bad news but as you are now pregnant and with the problems you have had in life so far this is a serious situation and you really need to get some professional help & advice

Start with the citizens advice bureau, you can find the number in the yellow pages

I really wish you good luck but you have to be realistic and accept that it is going to be extremely difficult for him to come back here and that maybe he will not be able to come back at all

I'm sorry but thats the truth