I have a following two questions which are connected.
1- Is it halal for a Muslim man or women to marry a Muslim man or women with HIV positive? My reason for asking is that the one who is HIV negative is putting his/her into danger of getting that HIV because as per my understanding Islam doesn't encourage to hurt yourself. There can be some Muslim man/women who did something bad and now they have asked Allah for forgiveness.
2- Is it alright to help some HIV positive male/female in finding life partner. I think answer of this will depend on first one. I am talking about those HIV positive who wants to come back in normal life and forget about their mistakes and they have asked Allah for forgiveness.
First, as I understand it, we cannot assume that every HIV positive person has got HIV as the result of doing something that was religiously forbidden.
Second, we should not do anything with the intention of harming ourselves. Marrying an HIV positive may make the person exposed to the risk of getting HIV, but this does not mean that the person had intention of harming himself.
Therefore my answer to both your questions is Yes. As for question 2, not only the answer is Yes but in fact it will be a very rewarding thing to do (i.e. finding a partner for a fellow human being who has difficulties in finding one because of a disease.)
The only important point to observe is that the person who is HIV positive should let his/her future spouse know about his/her condition well before marriage. In other words there shouldn't be any chance of deceiving someone into marriage.