It *could* be that your battery has given up the ghost - even if it has been on a tender.. I'd try jumping with a car battery, or, if you have a multimeter, try this simple test:
1) With key switch "OFF" measure voltage at the battery terminals - should be at least 12.5V (preferably more like 13) at rest with full charge.
2) Turn key to ON (light up the dash lights and headlamp) and recheck the voltage - if it has dropped to 11 volts or less, the battery isn't working at full strength - possible internal (partial) short of a cell or two, or sulfation along the bottom of plates if wet cell.
3) IF the battery checks out and the cables (esp the big ground cable and the big cable to the starter motor) are not corroded and firmly connected - and you've already checked the relay- it may be that the starter is indeed in need or repair and/or cleaning. The Valeo motor has had a tendency to sometimes drop one of its permanent magnets (glued in place) such that it can lock up the rotor. But, it could be a dirty.dried up Bendix, or faulty solenoid.
