When one partner in a relationship is HIV-positive, there are likely to be some difficult issues to deal with. Most couples, however, deal well with the situation after some time. The risk of the HIV-negative partner becoming infected is very low if you practice safer sex - and, in an emergency, by PEP.
The fear of passing on HIV is likely to be more of an issue at the beginning of the relationship. There may be some feelings of guilt or blame , especially if the positive partner has become infected by someone else during the course of the relationship.
On the other hand, sometimes the HIV-negative partner will treat their partner as if they were dangerously ill – although the positive partner would much prefer to be treated normally.