Why do I want a baby so much ?

You've answered the question yourself, you have very little family- you must miss love and unconditional attention. You're 16 with a long term partner, you're starting to think this may be pheasable (but it's not). You live in a B+B must be lonely? I'd concentrate on the future and try and put this idea to bed as no matter how good it seems an idea now, it just won't work out and you'll regret it later in life. There is so much to look forward to no matter how things feel at the moment.