Infidelity Support Group
Any relationship in which one partner engages willfully in sexual relations with another outside of the partnership is considered to have experienced infidelity. This breach of trust is often traumatizing for the faithful partner as well as the relationship, and support is often needed to heal emotionally and to decide whether or not the relationship should continue after...
You aren't paranoid.
Also, you need to let him know how this relationship with the other woman makes you feel.
If she is giving him money and gifts, there is something else going on there, just my opinion of course.
What would he think if you had a male friend that gave you money and gifts?
Maybe that would be a good question to ask him.